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+--------------------------------------------------------------------+
| |
| A S I C 3.00 |
| |
| "Its Almost Basic" |
| |
| |
| Copyright 1991 |
| by |
| David A. Visti |
| |
| All Rights Reserved |
+--------------------------------------------------------------------+
| ASIC 3.00 is provided as shareware. Under the shareware concept, |
| you can test a program before you buy it. If you find it suitable |
| for your needs and make use of this program, you are expected to |
| send a $10 registration fee. |
| |
| Feel free to distribute this software to others. However, you |
| may not charge for the distribution of this software to others |
| nor may you alter the software or this documentation. |
| |
| Registered users of any version of ASIC will receive a diskette |
| containing the current version of ASIC, plus may purchase future |
| updates at half of the normal registration price. A printed |
| manual is available to registered users for an additional $10.00. |
| |
| For further ordering information, please see the file ORDER.FRM, |
| included with ASIC. |
+--------------------------------------------------------------------+
| |
| Please send registration fees and suggestions to: |
| |
| David Visti |
| P.O. Box 2952 |
| Raleigh, NC 27602-2952 |
| |
| Please mention the version of ASIC in any correspondence |
| (This is ASIC Version 3.00) |
+--------------------------------------------------------------------+
| I can also be reached for questions/comments on GEnie and |
| Compuserve via EMAIL: |
| |
| Compuserve 73065,1302 |
| GEnie D.VISTI |
| |
+--------------------------------------------------------------------+
| |
| DISCLAIMER: This software is provided "as is" without warranty |
| of any kind. In no event shall I be held liable for any damages |
| whatsoever arising from the use of or inability to use this |
| product. |
| |
| Your registration fee entitles you to use this software on a |
| single computer. Site licenses are available, write for details. |
+--------------------------------------------------------------------+
A S I C
Table of Contents
Chapter Title
1. Getting Started Page 3
2. Tutorial Page 5
3. Integrated Editor/Compiler Environment Page 11
4 Using the Debugger Page 22
5. Stand-alone Compiler Options Page 30
6. Language Elements Page 33
7. Keyword Reference Page 39
ABS Page 39
ASC Page 39
BEEP Page 40
BLOAD Page 41
BSAVE Page 42
CALL Page 43
CHDIR Page 44
CHR$ Page 45
CLOSE Page 45
CLS Page 46
CODE Page 46
COLOR Page 47
COMMAND$ Page 48
COMSTAT Page 49
CSRLIN Page 50
DATA Page 51
DATE$ Page 52
DEFSEG Page 52
DIM Page 53
END Page 53
ENVIRON$ Page 54
FILEPOS Page 55
FIND Page 57
FOR/NEXT Page 59
GETDIR Page 60
GOSUB Page 61
GOTO Page 61
IF/THEN/ELSE/ENDIF Page 62
INKEY$ Page 64
INP Page 64
INPUT Page 65
INPUT# Page 66
INSTR Page 68
INT86 Page 69
KILL Page 71
LCASE$ Page 71
LEFT$ Page 72
LEN Page 72
LOCATE Page 73
LPRINT Page 73
LTRIM$ Page 74
MID$ Page 74
MKDIR Page 75
Page - 1
Table of Contents (Continued)
Chapter Title
7. Keyword Reference (Continued)
MOD Page 75
NAME Page 76
OPEN Page 76
OPENCOM Page 77
OUT Page 78
PEEK Page 78
POINT Page 79
POKE Page 80
POS Page 80
PRESET Page 81
PRINT Page 81
PRINT# Page 82
PSET Page 84
RANDOMIZE Page 84
READ Page 85
RECEIVE Page 86
REM Page 87
RESTORE Page 87
RETURN Page 88
RIGHT$ Page 88
RMDIR Page 89
RND Page 90
RTRIM$ Page 91
RUN Page 92
SCREEN Page 93
SEND Page 94
SOUND Page 94
SPACE$ Page 95
STR$ Page 95
STRING$ Page 96
TIME$ Page 97
TIMER Page 98
UCASE$ Page 99
VAL Page 99
VARPTR Page 100
WHILE/WEND Page 100
WIDTH Page 101
ZBIT Page 101
ZMODE Page 102
8. Compatibility with BASICA/GWBASIC Page 103
9. Technical Details/Tips Page 106
10. Error Messages Page 111
Page - 2
A S I C
Chapter 1
Getting Started
INTRODUCTION
Welcome to ASIC!
ASIC is a "BASIC" programming language compiler for IBM PCs and
compatibles. It includes an integrated full screen editor, from which
you can edit, compile, and debug your programs. Or at your option, you
can use your own text editor, and compile your programs from the MS DOS
command line.
ASIC is a subset of BASICA and GWBASIC which supports over 80 BASIC
statements, integer and string variables, and integer arrays. It will
compile your programs at high speed, and the code it generates is fast
and compact. The syntax of each ASIC statement is generally a valid
subset of the syntax used by BASICA and GWBASIC (exceptions are noted in
Chapter 8.)
All you need to get started is:
1) ASIC
2) IBM PC or 100% Compatible
3) 305-405k Available Memory*
4) Two floppy disk drives
<or>
One hard disk drive and one floppy disk drive
The first step is to install ASIC as described below. Then,
proceed to Chapter 2 for a brief ASIC tutorial. Following that you can
read the remainder of the documentation straight through, or refer to it
as you need it. Have Fun!
* The ASIC Compiler will run in 305k of memory. The ASIC Editor
will run in less than 200k of memory, however, to compile and
debug within the editor, 405k of available memory is required.
If ASIC does not find sufficient memory to call the compiler
from within the editor, it will ignore the compile
request and return to the editor.
Page - 3
INSTALLATION
To install ASIC execute the following commands as appropriate for your
machine. The procedure to do so is provided below for both floppy
systems and hard disk based systems. Also refer to the README file on
your ASIC Diskette for additional information.
TWO-FLOPPY DISK SYSTEM INSTALLATION
1) Make sure that the following files are all on the same diskette (the
diskette that contains these files will be referred to in this manual as
the "Compiler" diskette):
ASIC.EXE
ASICC.EXE
ASIC.IDX (Optional)
ASICM.IDX (Optional)
ASIC.DOC (Optional)
(Note: The optional files are required if you wish to use the
extended online help feature).
2) Format one or more blank diskettes to hold your programs (these
diskettes will be referred to in this manual as your "Program"
diskettes):
Note: Whenever you see the symbol <enter> in this
document, this refers to the <enter> or <return> key
on your keyboard.
HARD DISK SYSTEM INSTALLATION
1) Type: C: <enter>
2) Type: MD C:\ASIC <enter>
3) The next step is to copy the ASIC software to the ASIC directory.
If your ASIC software is on a floppy, insert the floppy in Drive
A: then type the command:
COPY A:*.* C:\ASIC <enter>
If your ASIC software is already on a hard disk directory, copy
it to the ASIC directory with the command:
COPY C:\directoryname\*.* C:\ASIC <enter>
Note that ASIC will run from any subdirectory, however, the
tutorial assumes ASIC is under C:\ASIC
Note: Whenever you see the symbol <enter> in this
document, this refers to the <enter> or <return> key
on your keyboard.
Page - 4
A S I C
Chapter 2
Tutorial
ASIC programs look very much like regular "BASIC" programs which you are
probably already familiar with. The one very noticeable difference is
that ASIC programs have no line numbers. Let's take a look at a very
simple program written both in GWBASIC/BASICA and in ASIC:
GWBASIC/BASICA ASIC
--------------------------+----------------------------------
|
10 I=I+1 | ADDONE: I=I+1
20 PRINT I | PRINT I
30 IF I<100 THEN 10 | IF I<100 THEN ADDONE:
--------------------------+----------------------------------
Both of these programs do the same thing. They display the numbers
from 1 to 100. However, notice that ASIC allows you to use descriptive
labels (ADDONE) instead of a line number (10). These labels can be up
to 80 characters long! Also note that the ASIC "PRINT" and "IF"
statements were indented only for increased program readability. The
ASIC program could just as well have been written as:
ASIC
------------------------------
ADDONE:I=I+1
PRINT I
IF I<100 THEN ADDONE:
------------------------------
We could have made our variable names longer. Instead of "I" we
could have chosen "SECONDS" or "VELOCITY", or some other name up to 80
characters in total. In ASIC, variable names, labels, and string
constants can all be up to 80 characters in length.
Well, now that we've seen a basic ASIC program, let's try to enter
and run a slightly larger program. The program we will be working with
will print the message "HELLO yourname" in 256 color combinations. If
you have a monochrome display card, don't worry, the program will work,
but instead of seeing different colors you'll see characters with
different attributes, such as blinking, underlined, etc.
Let's get started. If you haven't done so already, install ASIC as
described in Chapter 1. Now then, writing an ASIC program involves
these three steps.
1. Write your program.
2. Compile your program.
3. Run/Test your Program.
Page - 5
These three steps can all be performed from within the ASIC
Integrated Environment. Before we proceed with our "Hello yourname"
Program, let's go over some conventions.
In the following section:
FLOPPY TYPE--> Means that only 2-floppy disk system users
should type this line.
HARD TYPE--> Means that only hard disk system users
should type this line.
TYPE--> Means that both floppy and hard disk users
should type this line.
X> This is a representation of the prompt from
PC-DOS or MS-DOS. Floppy Disk Users will
actually see "A>" for a prompt. Hard Disk
Users will see "C>" for a prompt.
<enter> Means that you should press the <enter>
or <return> key on your keyboard.
<?> Text enclosed between the "<" and the ">"
symbols indicate a key to type. Don't type
the "<" or ">" symbols. For example, if the
tutorial lists "<F1>", your should press the
"F1" key on your keyboard.
NOTE: Floppy Disk users need to insert their ASIC Compiler diskette in
Drive A: at this point, and a Program diskette in Drive B: (See the
Installation section for more information)
Let's begin:
FLOPPY TYPE--> A: <enter>
HARD TYPE--> CD C:\ASIC <enter>
The computer should respond:
X>
Now enter the command to invoke ASIC:
TYPE--> ASIC <enter>
You are now in ASIC. The top line is the Menu Bar. The bottom line is
the Status Line. Chapter 3 describes this in more detail. For now,
we'll just describe a couple of features on these lines.
The status line indicates that the current mode is "INSERT". This means
that any characters you type on a line will be inserted between the
existing characters. If you press the <INS> key on the keypad, ASIC
will toggle to its other mode, OVERSTRIKE. In this mode, when you type
Page - 6
a character, it overlays the character that was there before. Each time
you press the <INS> key, ASIC will toggle between the INSERT and
OVERSTRIKE modes.
You can open the menus listed on the "Menu Bar" by holding down the ALT
key while typing the Capitalized letter of the menu you wish to open.
For example, to open the File menu, press <ALT><F>. Try it now:
TYPE--> <Alt><F>
The "File" menu will pop open. You can select a menu option from that
menu by typing the capitalized letter of the option, or by using the
arrow keys on your keypad to highlight the option you want and then
pressing <enter>.
If you are not sure what the menu option will do, you can press <F1> and
ASIC will display some help information for the highlighted menu option.
When you opened the File menu, the first option on that menu, "Open" was
highlighted. Let's get some help on "Open":
TYPE--> <F1>
ASIC will display some help information on "Open". Let's close the help
window now:
TYPE--> <ESC>
The help window will close. The <ESC> key will always let you escape
from any menu or help screen in ASIC, without taking any action. Let's
also close the file menu for now:
TYPE--> <ESC>
The "File" menu should have closed. By the way, in addition to the menu
help, ASIC provides additional online help. If you need general ASIC
help, press the <F1> key for a quick summary of some of ASIC's features:
TYPE--> <F1>
ASIC will display some general help. From this screen, we can also
retrieve additional information about BASIC statements such as PRINT or
GOSUB. Let's bring up an index of these statements.
TYPE--> <F1>
ASIC has opened a help index screen. From this screen we can use the
arrow keys to highlight any ASIC keyword and obtain more information for
that keyword by then pressing enter. We won't do that now, but don't
forget that this screen is available. Chapter 3 of the ASIC Reference
Manual describes all of the online "HELP" features available in ASIC and
provides a full description of the ASIC Editor Commands which are
available. Exit the help menu:
TYPE--> <ESC>
Page - 7
Entering a program in ASIC is simplicity itself. We'll simply type in
each line, pressing <enter> at the end of each line. If you make a
typing mistake, just use the arrow keys to move to the error, and type
in the correction. Use the <DEL> or <Backspace> keys to delete any
unwanted characters from the screen.
Make sure the status line says "Mode: Insert". This is the default mode
in ASIC. If it doesn't, press the <INS> key until it does. Now let's
enter our program (the program below intentionally contains an invalid
ASIC statement. We'll correct the line later in the tutorial, for now,
type in the program exactly as it's listed below):
TYPE--> CLS <enter>
TYPE--> PRINT "Please enter your name"; <enter>
TYPE--> INPUT YOURNAME$ <enter>
TYPE--> FOR I=1 TO 16 <enter>
TYPE--> FOR J=1 TO 16 <enter>
TYPE--> COLOR I,J <enter>
TYPE--> PRINT "HELLO "; <enter>
TYPE--> PRINT YOURNAME$; <enter>
TYPE--> NEXT J <enter>
TYPE--> NEXT I <enter>
TYPE--> CLS <enter>
TYPE--> THE END <enter>
There, that was easy. Now, let's compile our program. To do it, we'll
open the "Compile" menu, and select the "Compile program" option:
TYPE--> <ALT><C>
The "Compile" menu will pop open. The first option, "Compile program"
can be selected by typing the option letter which is capitalized "C", or
by moving the highlight bar to this option and pressing the <enter> key.
Since the highlight bar is already on this option, let's just press
<enter>:
TYPE--> <enter>
Since we didn't specify a file name when we invoked ASIC, ASIC will now
ask for a file name (so it can save your program before calling the
compiler):
FLOPPY TYPE--> B:TUTOR.ASI <enter>
HARD TYPE--> TUTOR.ASI <enter>
Note that ASIC requires that your programs be stored in files ending
with the extension ".ASI". Had we entered "TUTOR" for our program name,
ASIC would have appended the letters ".ASI" for us. If we tried to
provide a different extension, such as "TUTOR.SRC", ASIC would display
an error message. Also, whenever you are presented a dialog box where
you are asked to enter text (such as file name, or Yes/No responses to
questions), you must press the <enter> key before ASIC will accept the
input.
Once you select the "Compile program" option, you'll see the ASIC
compiler screen appear. It will display a count of the lines compiled,
and when it is done, it will return to the ASIC editor.
Page - 8
If it detected any errors, it will display the first error message at
the bottom of the editor screen. It will also highlight the line in
your program which is in error. In this case the line "THE END" was
flagged with the error message "Syntax Error". Of course, that line
should have been entered simply as "END".
That should be easy enough to fix. Let's exit the error menu by
pressing the <ESC> key:
TYPE--> <ESC>
The error menu has disappeared, and our cursor is now on the erroneous
line. To fix the line:
TYPE--> <DEL><DEL><DEL><DEL>
That should do it. The last line of our program should now read "END".
Before we continue, let's assume we new the name of the END command, but
could not remember the proper syntax for it. ASIC provides an online
lookup for each ASIC statement. With the cursor positioned somewhere on
the word "END":
TYPE--> <Ctl><F1>
ASIC should have opened a help window describing the "END" statement.
To return to your program press the <ESC> key.
TYPE--> <ESC>
The help window should have disappeared and you should see your program
displayed again. Let's recompile the program:
TYPE--> <ALT><C>
TYPE--> <enter>
This time you should see the message "No Compiler Errors". If you
didn't, check your spelling and recompile the program until you receive
this message. Press <ESC> to remove the "No Compiler Errors" Window.
Now let's run the program. To do so, we'll open the "Run" menu, and
select the "Run your program" option.
TYPE--> <ALT><R>
TYPE--> <r>
This time, we just entered the capitalized letter from the menu option
"Run your program". Your computer screen should now prompt you to
"Please enter your name?". Go ahead and enter your name now:
TYPE--> yourname <enter>
You should see "HELLO yourname" printed in various color combinations,
and then the ASIC editor screen will reappear. Well, that's all there
is to writing, compiling, and running an ASIC program. Now, to exit
ASIC, open the "File" menu and select the "eXit" option.
Page - 9
TYPE--> <ALT><F>
TYPE--> <X>
You should see your MS DOS prompt once again. By the way, now that
you've successfully compiled the program, you can execute it directly
from MS DOS. Let's try it:
HARD TYPE--> TUTOR <enter>
FLOPPY TYPE--> B:TUTOR <enter>
Well, that's a brief introduction to ASIC! Next, you might want to read
Chapter 3, "Integrated Editor/Compiler Environment" to learn about the
many other features available in the ASIC editor. Following this you
should read Chapter 4 which explains how to use the ASIC Debugger.
Chapter 4 includes another short tutorial in which you debug a program.
The remaining chapters provide reference material which you can
either read, or just refer to as needed. Chapter 5 explains how to
compile programs directly from the command line of DOS. Chapters 6-8
describe the BASIC statements which are supported by ASIC. Chapter 10
provides more descriptive information for ASIC error messages.
Hope you enjoy programming in ASIC!
Page - 10
A S I C
Chapter 3
Integrated Editor/Compiler
Environment
INTRODUCTION
The ASIC integrated environment lets you edit, save, compile, and
debug your ASIC programs without ever leaving ASIC! This chapter will
explain the usage of the integrated environment.
ASIC SCREEN CONTENTS
ASIC divides the screen into three parts. The top line is called
the "Menu Bar". All of the menus available to you are listed on this
line. The bottom line is called the "Status Line". It continuously
displays some important program information. The middle 23 lines are
the "Edit Window". This is the section of the screen where you can make
changes or additions to your program.
MENU BAR PROCESSING
Currently, there are four menus available. The "File" menu allows you
to load/save your existing program files to/from disk. It is also used
to exit ASIC. The "Edit" menu contains various editing commands which
are available. The "Compile" menu is used to compile your program, set
compiler options, and to view compiler errors. The "Run" menu allows
you to run your programs, and test them using the ASIC debugger.
To open a menu, hold down the <ALT> key and type the first letter
of the menu. The menu will pop down and display the options available
on that menu. If you want to close the menu without taking any action,
press the <ESC> key. If you wish to open a different menu without first
closing the current menu, press the left or right arrow keys.
Otherwise, to select an option, type the capitalized letter of the
menu option. For example, on the "File" menu, to select the "eXit"
option, type an "X" or an "x". Another way to select an option is to
move the "Highlighted Bar" down to the option you wish to select, and
press the <enter> key.
Some functions may be accessed outside of the menus with function
keys. These are listed on the menus (eg. "search Again <F3>" on the
Edit Menu), however, these function keys do not operate when a menu is
open. (A list of these Function keys is presented later in this chapter
in the Keyboard Usage Section).
Page - 11
GETTING HELP
ASIC provides "online" help within the integregated environment to
assist you with keyboard usage, menu options, and ASIC keywords. This
section tells you how to access this online help.
General Help
General describes the usage of the keyboard in ASIC. Keyboard keys
which perform ASIC functions are described in this section. Access
general help by pressing Function key <F1>. Pressing <F1> a second time
will display an ASIC keyword index. You can get additional help on
individual ASIC keywords from this screen. This information includes a
description of what the keyword does, and the keyword syntax.
Menu Help
If you open a menu, but you are not sure what a certain menu option
does, you may display a description of the highlighted menu option by
pressing the <F1> key. Doing so will open a help window which describes
the menu option. Press <ESC> to exit the help screen and return to the
menu.
Keyword Help
Can't remember the syntax for a particular ASIC keyword? Well, help is
just a keystroke away. Position the cursor on the keyword in the edit
buffer. Then, hold down the <Ctl> key and press the <F1> key.
ASIC will display a description of the keyword, and describe proper
syntax for that keyword. For example, if you tried to compile a
program, but received a syntax error on the keyword "PRINT" in your
program, you could obtain help on the "PRINT" statement by using the
arrow keys to position the cursor anywhere on the word "PRINT" and then
pressing <Ctl-F1>. If ASIC cannot find the keyword (eg, say the cursor
was positioned on a variable called "APPLES", which is not an ASIC
keyword), then ASIC will display a list of valid keywords. Use the
cursor keys to highlight one of these keywords and press <enter> to
retrieve help for the highlighted keyword. You may also access this
keyword help list by pressing the <F1> key twice from within the editor.
Now let's describe the options available on each menu.
FILE MENU
"Open" Option
This option allows you to open an existing ASIC file and load it
into the ASIC edit buffer where you can modify it. If you select this
option another window will open to ask you the file name. If you don't
wish to open a file, you can press <ESC> to close the menu without
taking any action. Otherwise, enter an ASIC file name, and press the
<enter> key.
Page - 12
FILE MENU (Continued)
"Save" Option
This option allows you to write the changes you've made to your
program back to the file. Changes you enter in the ASIC editor are made
to memory only. You must select this option before your changes will
become permanent. Note: Your file is saved to disk automatically
whenever you compile it or run it, if the file modified indicator is
set.
"save As" Option
This option will allow you to write the changes you've made to the
program in the edit buffer to a new file. You will be prompted to
provide ASIC with a new file name.
"eXit" Option
This option will allow you to exit from ASIC back to MS DOS. ASIC
will ask you if you wish to save your file before you exit.
EDIT MENU
"Begin block" Option
This option will allow you to mark the beginning of a block of text
for use with the block delete, copy, and move commands. To mark a block
of text, move the cursor to the first line of the block, and then select
this option. The beginning line of the block will be highlighted on the
screen. Next, move the cursor to the ending line of the block, and
select the "End block" option from this menu. All of the lines in the
block will be highlighted. This block of lines can now be "moved",
"copied", or "deleted" using the block commands.
"End block" Option
This option will allow you to mark the end of a block of text.
Refer to the "Begin block" Option for more information.
"Search" Option
This option allows you to locate a string of characters in the edit
buffer. When you select this option, ASIC will ask you for a search
string which can be up to 30 characters in length. ASIC will then
search forward from the current line until it finds the string or
reaches the end of the edit buffer. If it finds the string, the cursor
will be placed on the line containing the string.
Page - 13
EDIT MENU (Continued)
"Replace" Option
This option will allow you to replace one or more occurrences of a
string of characters with another set of characters. When you select
this option, ASIC will ask you for a search string which can be up to 30
characters in length. ASIC will then ask you for the string of
characters which is to replace the search string. Finally, ASIC will
ask you to specify how many occurrences of this search string are to be
replaced (from 1-9999). ASIC will search forward from the current line,
and briefly display each line as it modifies it. If it reaches the end
of the edit buffer before it has replaced the number of occurrences
you've specified, ASIC will display an "End of Buffer" message, and
stop.
"Delete block" Option
This option will delete a block of lines. Refer to the "Begin
block" option for information on marking a block of lines. If you
haven't marked a block of lines, selecting this option will have no
effect.
"Move block" Option
This option will move a block of lines to a new location in the
edit buffer. Refer to the "Begin block" option for information on
marking a block of lines. If you don't mark a block of lines, selecting
this option will have no effect. Once you have marked a block of lines,
move the cursor to the location in the edit buffer where you want the
lines moved. Selecting the "Move block" option will result in the block
of lines being deleted from their current location, and moved to the
buffer at the line following the cursor. ASIC will not overlay lines,
it will insert enough blank space to hold the relocated text.
"Copy block" Option
This option is the same as the "Move block" option, with one
exception. After moving the block, ASIC does NOT delete the original
block of lines. Use this option to clone a block of text. Refer to the
"Begin block" option for information on marking a block of text.
"search Again <F3>" Option
This option will allow you to search for the next occurence of the
last string you searched for with the "Search" Option, without retyping
the previous search string. This option may also be selected outside of
the Edit Menu by pressing function key <F3>.
Page - 14
COMPILE MENU
"Compile program <F10>" Option
Use this option to have ASIC compile the program which is currently
loaded in the edit buffer. If the compile is successful, ASIC will
display the message "No Compiler Errors". Otherwise, it will display
the first error message (see "View compile errors" option). ASIC will
automatically save your program before calling the compiler. This
option may also be selected outside of the menu by pressing function key
<F10>.
"Full program listing" Option
This menu option, and the next four options are used to toggle
various compiler options on or off. When the option is on, you will see
a "check mark" symbol next to the option. This compiler option will
cause ASIC to display each source line as it compiles it. This option
will slow down the compile, but since ASIC also writes these lines to a
listing file, this option can be used to create a compile listing. The
compile listing will be contained in a file called "progname.LST", where
"progname" is the name of your program.
"Printer output" Option
This menu option will toggle the "Printer output" compiler option
on or off. When the option is on, you will see a "check mark" symbol
next to the option name. This compiler option will cause compiler
messages to be printed on your printer.
"Symbol table" Option
This menu option will toggle the "Symbol table" compiler option on
or off. When the option is on, you will see a "check mark" symbol next
to the option name. This compiler option will cause ASIC to create a
symbol table file called "progname.SYM", where "progname" is the name of
your program. The symbol table is a list of all variables, labels, and
internally created compiler addresses.
"Extended math" Option
By default, ASIC will permit regular integer variables. These
variables are very efficient and only require two bytes (or characters)
of memory storage. However, these integers can only hold numbers in the
range of -32767 to +32767. For many programs this is sufficient.
However, there may be cases when you want to represent larger integer
values. Because of this, ASIC provides a "long" integer data type. The
long integer requires four bytes of memory storage. However, it can
hold a much larger range of numbers. A long integer can store numbers
in the range of -2,147,483,647 to +2,147,483,647. When you need to use
long integers in your program, you need to turn on this option, so that
ASIC can generate the proper code. If this option is not turned on and
your program contains long integers, ASIC will generate a compiler
error. If this happens, just turn this option on, and re-compile your
program. To "create" a long integer variable or constant, simply append
the "&" character to the variable name or constant value(eg, SAMPLEVAR&
or 123456&). For further information on using long integers, refer to
Chapter 6, "Language Elements", of the ASIC Manual.
Page - 15
COMPILE MENU (Continued)
"Debugging code" Option
This menu option will toggle the "Debugging code" compiler option
on or off. When the option is on, you will see a "check mark" symbol
next to the option name. This compiler option will cause ASIC to
generate code required by the ASIC debugger to allow you to set
breakpoints, single step through your program, and view/modify program
variables. This option is "on" by default in the integrated
environment. You should leave this option on while you are debugging
your program. When you have everything working properly, you should
turn it "off" and recompile your program. This will reduce the size of
your program slightly, and will make it run faster (of course, you can't
use the debugger with it, since there is no debugging information
available to ASIC any more. If you need to debug your program again,
just recompile with the this option turned "on" again).
"View compile errors" Option
When you wish to examine the errors from a previous compile of your
program, select this option. If no errors exist, ASIC will so inform
you. Otherwise, ASIC will display the first error message at the bottom
of the screen, and it will highlight the line of your program which
corresponds to that error. If you wish to correct the program line,
press the <ESC> key. The cursor will be positioned at the beginning of
that program line. You may also view subsequent compiler errors by
pressing the <F10> key instead of the <ESC> key.
"Write options to disk" Option
Normally, when you set compiler options in the integrated
environment, they "exist" only for your editing session (ie, when you
leave the editor, ASIC resets the options to the defaults). If you
prefer, you may use this option to cause ASIC to write the current
session's options to a configuration file (ASIC.CFG). Then, when you
invoke the ASIC integrated environment, it will first check for this
configuration file. If found, it will use your saved configuration.
Otherwise, it will use the ASIC defaults. This configuration file is
not accessed by the command-line version of the compiler, so they only
take affect when you are inside the integrated environment.
Page - 16
RUN MENU
The "Using the ASIC Debugger" Chapter has additional information on
the debugger and it's options. You may wish to refer to it, should you
need more information than is provided below.
"Run your program <F5>" Option
After you have successfully compiled your program, you can select
this option to cause ASIC to load and execute your program. After your
program ENDs, ASIC will return you to the editor. ASIC will save the
edit buffer before loading and executing your program. If you are
running a program containing debugging code, this option will cause ASIC
to run your program up to the first breakpoint it encounters, or through
the end of your program if you haven't set any breakpoints. If you are
already "paused" at a breakpoint, selecting this option will cause your
program to resume execution at the statement following the breakpoint,
and run up to the next breakpoint or to the end of your program, if no
further breakpoints are encountered. This option may also be selected
outside of the "Run menu" by pressing function key <F5>.
"Breakpoint toggle <F9>" Option
If you have compiled your program with the "Debugging code" option
turned on, you may use this option to set breakpoints. You can have up
to 20 breakpoints active at a time. When you run your program with
breakpoints set, ASIC will pause your program when it tries to execute a
line on which you have set a breakpoint. At this time, you can view or
modify variables, or view the screen output produced by your program.
You can then resume program execution by selecting the "Run your
program" option from the run menu. If you select this option and the
current statement in the edit buffer already has a breakpoint set, then
the breakpoint for that source statement will be removed (toggled off).
Lines at which you have set a breakpoint will be displayed in reverse
video. Also, when you run your program and ASIC stops at a breakpoint,
ASIC will display the next line to execute in reverse video on the
second line of the screen with a red background (underlined if you have
a monochrome system). This option may also be selected outside of the
"Run" Menu by pressing function key <F9>.
"Trace <F8>" Option
If you have compiled your program with the "Debugging code" option
turned on, you may use this option to execute your program one statement
at a time. After you select this option, ASIC will execute the next
program statement in your program, and pause, displaying the next line
which will be executed in reverse video with a red background
(underlined if you have a monochrome system). At this time, you can
view or modify variables, or view the screen output produced by your
program. You can then resume program execution by selecting the "Run
your program" option from the run menu, or by selecting the "Trace"
option again. This option may also be selected outside of the "Run"
Menu by pressing function key <F8>.
Page - 17
RUN MENU (Continued)
"Modify variable" Option
If you have compiled your program with the "Debugging code" option
turned on, you may use this option to modify the contents of variables
in your program while your program is paused at a breakpoint or
following a "Trace" command. When you select this option, ASIC will ask
you for the variable name. After you enter the variable name, ASIC will
ask you for the new value to be stored in the variable. If the variable
is an array, ASIC will ask you which element of the array to modify.
"Watch variable <F6>" Option
If you have compiled your program with the "Debugging code" option
turned on, you may use this option to view the contents of variables in
your program, while your program is paused at a breakpoint or following
a "Trace" command. After you enter the variable name, ASIC will open a
"Watch" window at the bottom of the screen showing you the variable name
and the current value. As you continue execution of your program and
reach a new breakpoint, the values of variables will be updated to
reflect their new values. In this way you can watch the changing values
of variables in your program without inserting "PRINT variablename"
statements in your program. Up to 10 variables may be watched at a
time. If you enter a variable name which is an array, ASIC will ask you
which element of the array you wish to watch. This option may also be
selected outside of the "Run" Menu by pressing function key <F6>.
"Unwatch variable <F7>" Option
If you have compiled your program with the "Debugging code" option
turned on, you may use this option to remove variables from the "Watch"
window (see previous option). When you select this option, you will be
asked for a variable name to remove from the window. If the variable is
an array, you will also be asked which element of the array. ASIC will
then remove the variable from the watch window, and resize the window
accordingly. Since only 10 variables may be watched concurrently, you
may need to remove variables which are no longer needed from the "Watch"
Window using this command. This option may also be selected outside of
the "Run" Menu by pressing function key <F7>.
"Abort execution" Option
If you are running your program, and it is paused at a breakpoint,
you may select this option to abort the execution of your program. Your
program will be terminated immediately.
"Clear all break/watch" Option
If you have set breakpoints or watch variable options, you may use
this option to remove all of them at once, instead of removing them one
at a time using the "Toggle breakpoint" or "Unwatch variable" options.
Page - 18
RUN MENU (Continued)
"Program arguments" Option
This option allows you to pass command line arguments to your
programs, which may be retrieved by your program using the COMMAND$
statement. If you are testing outside the integrated environment, you
would normally specify the command line arguments by typing
"progname arguments". However, in the integrated environment, since
ASIC is executing your program for you, this option is a means to pass
the "arguments" to your program as if they had been typed on the command
line following your program name.
"Swap to user screen <F4>" Option
Whenever ASIC pauses your program at a breakpoint, it saves the
screen created by your program in a memory buffer. You may select this
option to view your program screen output. When you are done viewing
your program's output, press a key to return to viewing the ASIC editor.
This function may also be selected outside the "Run" Menu by pressing
the <F4> function key.
STATUS LINE
The bottom line of the ASIC screen is called the "Status Line". As
it's name implies, it is used to display various types of status
information. At the left of the status line "FILE: xxxxxxxx.xxx" will
display the name of the file which is currently loaded in the edit
buffer. If you haven't opened a file yet, the file name will be blank.
After the file name is the "File Modified Indicator". If you have
entered any changes in the edit buffer, and have not saved them to disk,
an "*" will appear to indicate this. If the edit buffer has not been
modified since the last save to disk, no "*" will be present.
The next piece of information is "Mode:". Mode will always display
one of two values: "Insert" or "Ovrstr". In "Insert" mode, any
characters you type in the edit buffer will be inserted at the cursor
position, and the characters to the right of the cursor will be shifted
to the right by one. In "Ovrstr" mode, any characters you type in the
edit buffer will overlay (and thus destroy) the character at the cursor
position. You can change back and forth between these two modes by
pressing the <INS> key on your keypad.
To the right of "Mode:" ASIC displays the number of bytes which it
allocated to the edit buffer. Divide this number by 81 to get a rough
idea of how many lines will fit in the edit buffer.
The "Line: nnnn" status indicator, will identify which line of the
file is being displayed. For example, if the display reads "Line: 100",
the line containing the cursor is the 100th line in the file. When ASIC
is reading or writing your program to/from disk, it will display a
running total of the number of records read/written in this field.
Page - 19
STATUS LINE (Continued)
The "Row:" and "Col:" numbers identify the relative position of the
cursor within the "Edit Window".
EDIT WINDOW
The edit window is the area of the screen where your program is
displayed. It displays up to 23 lines of your program at a time. You
can use the keys described below to manipulate the text in this window.
KEYBOARD USAGE
Most keys on the keyboard behave in ASIC just as you'd expect. The
key usages which might not be obvious are described here.
<ESC> Exit from any menu without taking any action.
<TAB> Move the cursor to the next "tab stop". Tab stops in
ASIC are fixed at every fourth column (4,8,12,etc).
<HOME> Move the cursor to the beginning of the current line.
<END> Move the cursor to the first blank character following
the last non-blank character on the current line.
<DEL> Delete the character at the cursor position.
<INS> Toggle between Insert and Overstrike Modes.
<PGUP> Display the previous "page" of the edit buffer.
<PGDN> Display the next "page" of the edit buffer.
<Ctl-PGUP> Display the first "page" of the edit buffer.
<Ctl-PGDN> Display the last "page" in the edit buffer.
<Backspace> Delete the character to the left of the cursor
position, and move the cursor one column to the left.
Page - 20
KEYBOARD USAGE (Continued)
<Up Arrow> Moves cursor up one line.
<Down Arrow> Moves cursor down one line.
<Left Arrow> Moves cursor left one column.
<Right Arrow> Moves cursor right one column.
<Alt-D> Delete the line containing the cursor.
<Alt-A> Add a line following the line containing the cursor.
<F1> Displays a help screen.
<CTL-F1> Displays help information for the keyword located at
the cursor postion.
<F3> Repeats the last "Search" command. See Edit Menu
Section of this chapter for more information.
<F4> Swaps the display to the output from your program
temporarily. See Run Menu Section of this chapter for
more information.
<F5> Runs your program. See Run Menu Section of this
chapter for more information.
<F6> Add a variable to the "Watch" Window. See Run Menu
Section of this chapter for more information.
<F7> Remove a variable from the "Watch" Window. See Run
Menu Section of this chapter for more information.
<F8> Execute a single statement of your program. See Run
Menu Section of this chapter for more information.
<F9> Toggle breakpoint on/off at the current edit buffer
line. See Run Menu Section of this chapter for more
information.
<F10> Compile your program. See Compile Menu Section of
this chapter for more information.
<enter> In Insert mode, pressing <enter> is identical to
pressing <Alt-A>. In OvrStr mode, pressing <enter>
is identical to pressing the <Down Arrow> key.
Page - 21
A S I C
Chapter 4
Using the Debugger
INTRODUCTION
The source level debugger in ASIC's integrated programming
environment helps you debug your programs by allowing you to "peek"
inside them as they're running. You can single step through your
programs, or select places in the program where you wish execution to
pause by setting breakpoints. Then, while the program is paused, you
can view or modify any of your program's variables, and also examine the
screen output created by your program.
All of the debugger's commands can be selected from the run menu,
and they are described in the "RUN MENU" Section of Chapter 3,
"Integrated Editor/Compiler Environment". Many of the debugger commands
may be selected outside the "Run" menu, by pressing a function key (eg,
<F5>,<F6>,etc). A complete list of the function keys available is
contained in Chapter 3, in the "KEYBOARD USAGE" Section.
This chapter explains how to use the debugger with a short tutorial
which guides you through a sample debugging session. The tutorial is
followed by a reference section which you should read after completing
the tutorial.
DEBUGGER TUTORIAL
The debugger tutorial follows the same format as the general
tutorial in chapter 2. You should complete (or at least review) the
general tutorial before taking the debugger tutorial.
This tutorial will use a program file provided with your ASIC
compiler package called "DBGTUTOR.ASI". If you are running from a hard
disk, make sure it is in the ASIC directory. If you are running from a
two-floppy system, make sure it is on the diskette in drive b:, with the
compiler in drive a:.
NOTE: Floppy disk users should verify that the ASIC compiler diskette
is in drive A: and the "DBGTUTOR.ASI" disk is in drive b: before
proceeding.
Let's get started:
FLOPPY TYPE--> A: <enter>
ASIC B:DBGTUTOR <enter>
HARD TYPE--> C: <enter>
CD C:\ASIC <enter>
ASIC DBGTUTOR <enter>
Page - 22
You should be in ASIC now, and you should see a source program. The
first few lines should contain:
dim scores(10)
data 55,33,877,99,44,101,21,88,105,1
rem DBGTUTOR.ASI
.
. (etc)
.
This sample program will sort an array of 10 scores into ascending
sequence. It uses a simple "bubble" sort algorithm. The "bubble" sort
algorithm simply steps through each element of the array and compares it
to its next higher neighbor. If its neighbor's value is less than its
own, the two values are swapped. It is necessary to execute this
process N-1 times where N= number of items to sort. Here's why. Let's
say the lowest value to be sorted was "1" and it is in array element
"10" (assume 10 numbers will be sorted). The first swapping pass will
result in the "1" being swapped from element 10 to element 9 of the
array. An additional 8 passes through the array are necessary to move
the "1" to array element number 1. This algorithm gets its name,
because the process of moving the elements has been compared to that of
bubbles slowly rising to the surface.
This program has a list of ten scores to be sorted. Line 5 of the
program will read the ten scores to an array called "Scores", and also
print the original values (before the sort) to the screen. Then two
loops will execute at statements 8 and 9 in the program to perform the
bubble sort as described above. Finally, after the sort is complete,
the sorted values will be displayed.
First, let's compile the program. When we plan to use the debugger, we
must set the "Debugging code" option on. This is done on the Compile
Menu. However, the default in the integrated environment is "Debugging
code" on. Let's take a look to be sure:
TYPE--> <Alt><c>
The compile menu should pop open, and you should see a check mark next
to the "Debugging code" option. If you don't, press the letter "D", and
a check mark should appear. Once you've verified that the option is on,
we can compile the program. Notice that there is an <F10> next to the
option. Instead of opening this menu and selecting the "Compile"
option, we could have pressed <F10>. Let's try it. First, let's close
the menu (Function keys don't work inside a menu):
TYPE--> <ESC>
The menu should have closed. Now let's compile using the function key:
TYPE--> <F10>
You should see the compiler screen pop up, and compile the program. No
errors should be detected. Now we're ready to test the program. First,
let's set a breakpoint so we can easily view the screen output, Use the
Page - 23
down arrow key to position the cursor on line 20 (the line number is
displayed on the ASIC status line). Line 20 should contain an "END"
statement. Let's open the run menu and set a breakpoint:
TYPE--> <Alt><r>
<b>
The "END" statement should now be displayed in reverse video. That
tells us that a breakpoint has been set there. Did you notice that the
breakpoint option on the menu also had a function key listed. We could
set a breakpoint without opening a menu, by pressing <F9> instead. Now
that we've set a breakpoint, let's run the program and see how it works:
TYPE--> <Alt><r>
<r>
Note that we could have pressed the short cut key of <F5> to run the
program instead of selecting the option from the menu. At this point
our program is running, but is paused at the breakpoint we set on line
20. When you reach a breakpoint, ASIC will position the breakpointed
line on the second line of the edit window, highlighted in red (or
underlined, if you have a monochrome system). ASIC has interrupted the
program before it executed the line with the breakpoint, in this case
"END". Let's take a look at the screen output of the program to see if
it worked:
TYPE--> <Alt><r>
<s>
Note we could also select the "Swap" function by pressing <F4> without
opening a menu. You should now see the output from the program on the
screen. It should look something like:
Original Scores:
55 33 877 99 44 101 21 88 105 1
Sorting...
Here are the sorted scores:
33 55 99 44 101 21 88 105 1 877
Well, that doesn't look quite right. Maybe we can use the debugger to
figure out what went wrong. First, let's allow the program to run to
completion (remember, we're paused at a breakpoint on the "END"
statement). Swap back to the ASIC screen from the user screen by
pressing any key:
TYPE--> <enter>
You should see the editor screen again. Now let's tell ASIC to resume
program execution:
TYPE--> <Alt><r>
<r>
ASIC has executed the END statement, and our program has terminated.
You should see the message "Program Terminated Normally (0)". (The "0"
is the return code set by the program. You can set return codes in your
Page - 24
programs using the END statement. Refer to Chapter 7 for details.).
Now we'll set another breakpoint in the program. Move the cursor to
line 7 (the status line should now say LINE: 7) using the arrow keys.
The cursor should now be positioned on the statement which says: PRINT
"Sorting...". Set a breakpoint here:
TYPE--> <F9>
The source statement should now appear in reverse video. We used the
shortcut key <F9> to set the breakpoint this time, but you could have
opened the Run Menu, and selected the Breakpoint option and done the
same thing. Let's remove the breakpoint:
TYPE--> <F9>
Line 7 should no longer be highlighted. The same command is used to
turn breakpoints on or off for a source line. ASIC just checks to see
if a breakpoint is already set at that source line when you select the
breakpoint command. If one is set, it "toggles" it off (ie removes it),
otherwise, it "toggles" it on (ie sets a breakpoint). This exercise was
just to show you how to remove a breakpoint, let's go ahead and set it
again:
TYPE--> <F9>
Line 7 should be highlighted again (the breakpoint is set).
It might be nice to see what's in some of our program's variables, so
let's "watch" some variables. Open the Run Menu, select the Watch
command, and tell ASIC you want to watch variable "I".
TYPE--> <Alt><r>
<w>
i<enter>
ASIC should have opened a "Watch" window at the bottom of the screen.
You should see the variable name "I" at the left, followed by a ":".
Following the ":" is the current value of that variable. The number
there now doesn't really mean anything, since our program is not
running. But once the we start the program, this number should
represent the actual value of the variable "I".
Let's watch a few more variables: j, j1, and scores(1). This time,
we'll use the shortcut key for the watch command:
TYPE--> <F6>
j<enter>
Variable "J" should now be in the watch window.
TYPE--> <F6>
j1<enter>
Variable "J1" should now be in the watch window. When we watch
"scores", we'll also have to tell ASIC which element we want to watch by
entering a subscript, since "scores" is an array. First ASIC will
prompt you for the variable name. Type it, without the subscript. ASIC
will prompt you for the numeric subscript.
Page - 25
TYPE--> <F6>
scores<enter>
<1><enter>
Scores(1) should now be in the watch window. Now we're ready to run the
program again:
TYPE--> <F5>
Again we selected the short cut key, you could have selected the "Run
your program" option from the "Run" Menu. The second line of the edit
screen should show the PRINT "Sorting..." statement (highlighted in red,
or underlined if you have a monochrome monitor). The variables in the
watch window should have the following values:
I: 11
J: 0
J1: 0
SCORES(1): 55
Let's execute the next statement by using the Trace command:
TYPE--> <Alt><r>
<t>
ASIC has executed the PRINT "Sorting..." statement and has paused
execution on the "FOR I" statement on line 8 of the program. Since the
PRINT statement did not modify any variables, the numbers in the watch
window should remain unchanged. Let's Trace one more statement, this
time, we'll use the short cut key:
TYPE--> <F8>
ASIC has executed the "FOR I" statement on line 8, and is now paused on
statement "FOR J" on line 9 of the program. Something looks wrong
though. Even though we executed the first "FOR I" statement, the
variable "I" still contains "11". It should contain "1". If you look
at line 8, you'll see that the FOR statement was mistyped, it reads:
"FOR I = I to 9", instead of "FOR I=1 to 9". Since the program also
used variable "I" to READ the data into the array, "I" still contains
the value "11". Since "11" is greater than the "TO" value of the "FOR"
loop, the FOR loop on line 8 is executed only 1 time instead of 9 times.
That's why the data is not being fully sorted. With the ASIC debugger,
we can continue testing without recompiling, by modifying the value of
"I" to "1", so we can see if the rest of our logic is correct. If
changing "I" to "1" works, then we can go back and modify the "FOR"
statement and recompile the program to correct the program permanently.
Modify the value of "I" to "1":
TYPE--> <Alt><r>
<m>
i<enter>
<1><enter>
Page - 26
The watch window should now show the value of "I" as 1. We can resume
program execution at this point by selecting the "Run your program"
option. We'll use the short cut key again:
TYPE--> <F5>
ASIC should pause the program at the next breakpoint, which is on line
20. This statement contains the "END" command. Now let's see if the
program worked, by swapping to the user screen:
TYPE--> <F4>
Again, we used the short cut key. You should see the following on your
screen:
Original Scores:
55 33 877 99 44 101 21 88 105 1
Sorting...
Here are the sorted scores:
1 21 33 44 55 88 99 101 105 877
It looks like the program worked. Let's return to the editor screen.
TYPE--> <enter>
Now we could press <F5> to resume execution and in this case terminate,
since the END statement is the next one to execute. But let's look at
another way to terminate a program. While at a breakpoint, you can
select the "Abort your program" option, which instructs ASIC to
terminate your program immediately, without executing any more of your
program. Let's try it:
TYPE--> <Alt><r>
<a>
ASIC should display the message "Program Terminated Normally (0)". At
this point, we'll just exit from ASIC, but normally, you would fix the
FOR statement using the editor, save the file, recompile the program,
and retest it to make sure the "bug" is really fixed.
TYPE--> <Alt><f>
<x>
You should be back at the DOS prompt now. That concludes the brief
introduction to the ASIC debugger. The rest of this chapter provides
some additional reference material for the debugger. Chapter 3 provides
additional information about each of the debugging commands.
Page - 27
DEBUGGER TIPS
1) WHEN YOU ARE DONE DEBUGGING YOUR PROGRAM, YOU SHOULD RECOMPILE
WITH THE "DEBUGGING CODE" OPTION TURNED OFF. Although your program
can run from the DOS command line with debugging code present, it
will increase the program size and execution times. Recompiling
with the "Debugging code" option off will insure your programs
will be smaller and faster.
2) Remember that the default option on the command line compiler is
"Debugging code" off. The default option in the integrated
environment is "Debugging code" on.
3) Breakpoints/Watches are automatically cleared when you
OPEN or COMPILE a file.
4) If you change source lines in a program while a program
is running, without recompiling, source statements will
not match executable code. Abort the running program
and recompile after making code changes.
5) Breakpoints are set in the edit buffer relative to the
beginning of the buffer. If you insert/delete lines in
the buffer, the breakpoints will still be set at the
same relative line number from the beginning of the
buffer.
6) ASIC takes over the INT 3 Interrupt vector for debugging
purposes. It re-installs the default vector when you
exit ASIC.
7) You must compile with the "Debugging code" option to use
source level debugging.
8) If you wish to run a program from the beginning again
while its already running, select the "Abort your
program" option from the Run menu. Then, select the
"Run your program" option.
9) If you select the Abort option from the Run menu, your
program's files will NOT be closed gracefully. That
is, data in the buffers will not be flushed to disk.
10) You may still run a program in the integrated environment that
has been compiled without the Debugging code option. You just
won't be able to use the debugging commands (eg,
Breakpoints/Watches).
11) Toggling a breakpoint on/off will clear any block of
text you had previously marked for editing (eg, MOVE,
COPY).
Page - 28
DEBUGGER TIPS (Continued)
12) When modifying array variables, make sure that the
subscript you specify is valid. For example, if you
"DIM A(10)", make sure the subscript you specify is in
the range of 0 to 10. ASIC does not check the range of
a subscript. If you specify a subscript that exceeds
the valid range for that variable, your program may
crash.
13) You can pass arguments to programs using the "Arguments"
option on the Run Menu. You may retrieve these options
in your program with the COMMAND$ statement. Using the
"Arguments" option is equivalent to specifying arguments
following the program name, when you run your program
from the DOS command line.
14) The compiler allows variable names up to 80 characters in
length. The debugger only uses the first 30 characters of a
variable name. When the debugger finds two variables whose names
are not unique within 30 characters, it will always select the
first one it finds (this applies to the Watch/Unwatch/Modify
Variables commands).
15) ASIC will allow you to set a breakpoint on a "FOR" statement.
However, you should be aware that the source statement containing
the "FOR" is executed only once (to initialize the loop). When
the "NEXT" statement executes, control transfers back to the line
following the "FOR", instead of the "FOR". For example, in the
following code fragment:
FOR I = 1 TO 3 <---Executes 1 time to initialize loop
PRINT I <---Executes 3 times
A=A+1 <---Executes 3 times
NEXT I <---Executes 3 times, loops back to
"PRINT I", not to "FOR I= 1 TO 3"
16) Because a single machine language instruction could span multiple
CODE statements, ASIC does not allow breakpoints on CODE
statements.
Page - 29
A S I C
Chapter 5
Compiler Options
COMMAND LINE SYNTAX
Invoke the command line version of the compiler as follows:
ASICC filename option1 option2 option3[...option7]
Where: filename is the name of the source program to be
compiled. This file must have the file
extension ".ASI", although the extension
may be omitted from the command line.
optionN specifies any options desired. No
options are required, but as many as
seven may be specified.
COMPILER OPTIONS
A total of six compiler switches are currently available for ASIC. Each
is described in detail below:
Switch Description
C CONTINUE--ASIC will not pause after messages are
issued, but will continue compiling.
Default: ASIC will pause after each error message.
Compilation will resume after you press
a key.
Page - 30
COMPILER OPTIONS (Continued)
Switch Description
L LIST ALL--ASIC will list each source line as it
compiles it.
Default: ASIC will list only source lines with
compile errors.
Comment: Use of this switch will slow compile
speeds slightly due to the additional
screen I/O.
P PRINTLIST--ASIC will echo all messages which
appear on the screen to the printer.
Output to the printer will be paged
with header lines identifying the
program name, and the date/time
compiled.
Default: ASIC will not send any messages to
the printer.
Comments: Even though output to the printer is
buffered, this option will slow compile
speeds considerably. The compiler typically
compiles only as fast as your printer
can print the messages. An alternative
to this switch is the DISKLIST option
described below.
D DISKLIST--ASIC will echo all screen messages to a disk
file named "progname.LST". The format is
the same produced by PRINTLIST. This allows
you to compile at higher speed, and print
the source listing later from the disk file
via the DOS print spooler.
Default: ASIC does not produce a ".LST" file.
S SYMTAB----ASIC will produce a formatted Symbol Table
in a file named "progname.SYM". The symbol
table contains a list of all variables,
labels, and internally created compiler
addresses.
Default: ASIC does not produce a ".SYM" file.
Page - 31
COMPILER OPTIONS (Continued)
E EMATH-----ASIC will enable the Extended Math Option.
When this option is selected, you may specify
long integers (eg, VELOCITY&, 123456789&,
etc) which can hold a larger range of values
(+2,147,483,647 to -2,147,483,647). This
option does increase the size of your ".COM"
file by a couple of hundred bytes.
Default: ASIC does not enable the Extended Math
Option.
X DEBUG-----ASIC will generate debugging code in the
".COM" file and a ".DBG" file for use by the
integrated environment debugger.
Default: ASIC does not generate debugging information.
Comment: If you are running from the integrated
environment, ASIC sets this option on by
default. You may turn it off in the Compile
menu, should you so desire.
COMPILE EXAMPLES
Example 1: Compile "MYFILE.ASI" with default compiler options:
ASICC MYFILE
Example 2: Compile "MYPROG.ASI", Listing all source lines, writing
a compile listing to a disk file for printing later. The
listing file will be called "MYPROG.LST":
ASICC MYPROG L D
Example 3: Compile "FILEX.ASI", don't pause for any errors, and
print the errors on the printer:
ASICC FILEX C P
Example 4: Compile "CRUNCH.ASI" and allow long (32 bit) integer
numbers:
ASICC CRUNCH E
Page - 32
A S I C
Chapter 6
Language Elements
CHARACTER SET
Symbol Description
* Multiplication
Example: A=B*C (multiply B by C, store result in A)
/ Division
Example: A=B/C (divide B by C, store result in A)
+ Addition
Example: A=B+C (add C to B, store result in A)
+ String Concatenation
Example: A$="AB"+"C" (A$ will contain "ABC")
= Assignment
Example: A=1 (A will be assigned the value 1)
= Equality testing
Example: IF A=1 THEN QUIT: (If the value stored in
(A equals 1 goto label QUIT)
- Subtraction
Example: A=B-C (Subtract C from B, store result in A)
" String Delimiter
Example: A$="the string is inside quote marks"
() Parenthesis -- Ignored by ASIC
Symbol Description
; Suppress Carriage Return/Line Feed with PRINT/LPRINT
# Used to identify file usage with PRINT#/INPUT#
, Comma, Ignored by ASIC
$ Distinguishes a String Variable from an Integer.
Example: ABC$ <---- String Variable
Example: ABC <---- Integer Variable
Page - 33
CHARACTER SET (Continued)
Symbol Description
: Distinguishes a Label from a variable name.
Example: START: <---Label name
& Distinguishes a "long" (32 bit) integer from a normal
integer (16 bit) variable or constant. Normal integers
can hold numbers in the range +32,767 to -32,767. Long
integers can hold numbers in the range +2,147,483,647
to -2,147,483,647. Note: You must compile with the
"Extended Math" Option enabled to use long integers.
Example: APPLES& <--Long Integer Variable
Example: ORANGES <--Normal Integer Variable
Example: 123457& <--Long Integer Constant
Example: 1234 <--Short Integer Constant
Page - 34
CONSTANTS, VARIABLES, AND LABELS
ASIC supports the following data types: Integer Constants, Integer
Variables, Long Integer Variables, Long Integer Constants, single
dimension Integer Arrays, single dimension Long Integer Arrays, String
Constants, and String Variables. Constants may be specified in decimal
(base 10), hexidecimal (base 16), or binary (base 2). The following
describes the restrictions for each data type.
INTEGER CONSTANTS Range +32767 to -32767
Example: -26
INTEGER VARIABLE Described by a variable name beginning with a
letter, followed by up to 79 additional letters
or numbers. It may contain a number in the range
+32767 to -32767.
Example: VELOCITY1
INTEGER ARRAY Described by a variable name beginning with a
letter, followed by up to 79 additional letters
or numbers. This name is followed by an
integer variable or constant for the dimension
of the array. Arrays must be dimensioned at the
beginning of the program. See the DIM statement.
Example: GROWTH (YEAR)
LONG INTEGER Range +2,147,483,647 to -2,147,483,647
CONSTANTS
Example: 3234457&
LONG INTEGER Described by a variable name beginning with a
VARIABLE letter, followed by up to 78 additional letters or
numbers terminated with a "&". Can contain
numbers in the range +2,147,483,647 to
-2,147,483,647.
Example: VELOCITY1&
LONG INTEGER Described by a variable name beginning with a
ARRAY letter, followed by up to 78 additional letters or
numbers, terminated with a "&". This name is
followed by an integer variable or constant for
the dimension of the array. Arrays must be
dimensioned at the beginning of the program.
See the DIM statement.
Example: GALAXY& (BILLIONSOF)
Page - 35
CONSTANTS, VARIABLES, AND LABELS (Continued)
HEXIDECIMAL Hexidecimal constants are constants which are
CONSTANT stated in base 16 instead of base 10 like normal
constants. These may be specified wherever you
can specify a decimal constant. Hexidecimal
constants in ASIC must be prefixed by "&hex". This
prefix should be immediately followed by a valid
normal or long integer constant. Hex constants
may contain up to 8 hexidecimal digits for long
constants, and 4 hexidecimal digits for normal
constants.
Example: &hexB000 <--equivalent to -20400
Example: &hexB& <--equivalent to 11&
Example: &hexFFFFFFFF& <--equivalent to -1&
Example: &hexB000& <--equivalent to 45056&
BINARY CONSTANT Binary constants are constants which are stated in
base 2 instead of base 10 like normal constants.
These may be specified wherever you can specify a
decimal constant. Binary constants in ASIC must
be prefixed by "&bin". This prefix should be
immediately followed by a valid normal or long
integer constant. Binary constants may contain
up to 32 binary digits for long constants or 16
binary digits for normal constants.
Example: &bin10 <--equivalent to 2
Example: &bin10101011& <--equivalent to 171&
STRING CONSTANT A group of 0-80 characters enclosed by quotation
marks.
Example: "This is a String Constant"
STRING VARIABLE Described by a variable name which begins with a
letter, followed by up to 78 additional
letters or numbers, terminated with a "$".
Can contain 0-80 characters.
Example: ADDRESS$
LABEL A Label is a location in your program you wish
to transfer to. It must begin with a letter,
and it may contain up to 78 additional letters
or numbers. It must be terminated with a ":".
Example: START:
Page - 36
VARIABLES VS. CONSTANTS
In general, ASIC will allow the use of either variables, arrays, or
constants as operands to any program statement. For example:
PRINT CASH
PRINT 20
PRINT A(10)
All three of the above examples are valid. The only case where a
constant cannot be used, is where the value is being modified. For
example:
A = A + B <----VALID
17 = A + C <----INVALID
Of course you must specify the correct data type for the ASIC keyword.
For example:
A = ABS("HELLO") <----INVALID
This statement is invalid because you cannot take the absolute value of
a string!
There are a few ASIC statements which will accept only integer constants
for some operands (DIM, OPEN, PRINT#, INPUT#). Refer to the individual
statement for more information.
Finally, there is a restriction on the use of subscripts for Arrays. A
subscript for an array cannot be another array. For example:
A(I(1)) <----INVALID
A(I) <----VALID
Page - 37
CONVERSION BETWEEN LONG/NORMAL INTEGERS
Long or normal integers may be used on any ASIC statement in any
combination. Consequently, in the "Keyword Reference" Chapter of this
is manual, operands are identified only as "integer". "Integer" in this
context should be interpreted as meaning that the operand for that
statement can be any of the following: integer constant, integer
variable, integer array, long integer constant, long integer variable,
or long integer array. Exceptions, if any, are noted in the
documentation for the statement.
If you do mix long and normal integers in a statement, you should be
aware of how ASIC converts between the two formats. The following two
rules are applied:
1) If a long integer variable or constant is being stored in a
normal integer variable, the long integer (32 bit) number
will ALWAYS convert correctly to a normal integer (16 bit)
value, provided the long integer variable contains a number
which will fit in a normal integer (ie, within the range of
+32767 to -32767). If, however, the number is outside of
this range, ASIC will truncate it to make it fit in a normal
integer. This truncation will cause some surprising (but
predictable) answers. For example if "A&" contained the
value "50000&", and the following ASIC statement was executed
"A=A&", then the value of "A" would be "-15536". The reason
that the overflow results in such a strange number is due to
the way the IBM PC stores numbers in binary format and is too
complicated to describe here. The important thing
to remember is, for ASIC to convert from long integers to
normal integers correctly, the value in the long integer
should be in the range of +32767 to -32767.
2) If a normal integer variable or constant is being stored in
a long integer variable, ASIC will always convert the number
correctly.
Page - 38
A S I C
Chapter 7
Keyword Reference
ABS
Format: integer1 = ABS (integer2)
Description:
This function returns the absolute value of integer2 which is then
stored in integer1.
Example:
A = ABS (-7)
After execution of this statement, "A" will contain 7.
ASC
Format: integer1 = ASC (string1)
Description:
This function returns the ASCII value of the first character of
string1, storing the result in integer1.
Example:
A = ASC("123")
After execution of this statement "A" would contain 49, which the is
ASCII value of "1".
Page - 39
BEEP
Format: BEEP
Description:
This statement will cause a short "beep" to be produced on the PC
speaker.
Example:
IF A>99 THEN
BEEP
PRINT "Number is too big!"
A=99
ENDIF
The preceding program fragment will check to see if variable "A"
contains a value less than 100. If it does not, it will produce a short
"beep", display a message, and set the value of "A" to 99.
Page - 40
BLOAD
Format: BLOAD string1, integer1, integer2
Description:
This function loads data previously saved by BSAVE from a file to
memory. String1 should be the name of the file previously created by
BSAVE. Integer1 should be the memory offset to load the data to.
Integer2 should be the number of bytes to read from the file (in the
range of 1 to 32767). If DEFSEG has been set, it will be used as the
data segment, otherwise, the default ASIC data segment will be used.
Example:
DEFSEG = &hexB800
BLOAD "SAVED.DAT" 0 100
After execution of these statements 100 bytes will be read from the file
"SAVED.DAT" and stored in memory start at 0 bytes from the start of the
override data segment (which in this case happens to point to the
beginning of video memory for a CGA card). Assuming a CGA card was
present, the first 50 characters on the screen would contain data read
from the file (don't forget that each screen character is represented by
two bytes data and attribute, that's why only 50 characters will be
displayed, assuming you are not in graphics mode).
Comments:
THIS FUNCTION IS RECOMMENDED ONLY FOR ADVANCED PROGRAMMERS. THIS
STATEMENT WILL ALLOW YOU TO OVERLAY ANY AREA OF MEMORY, AND IT IS VERY
EASY TO ACCIDENTALLY OVERLAY YOUR PROGRAM OR THE MEMORY USED BY DOS.
If ASIC detects an error executing this command, it will set the
system ERROR variable. These error codes are listed in the Error
Messages Chapter of the ASIC Manual
This statement is slightly different from GWBASIC/BASICA in that
you must specify how many bytes to read from the file. Also, the memory
offset is not stored in the file by BSAVE, so you must specify the
offset as integer1 in ASIC. Offset is optional in GWBASIC/BASICA.
ASIC uses a slightly different file format than GWBASIC/BASICA,
however, it is relatively easy to convert the GWBASIC/BASICA to ASIC
format. GWBASIC/BASICA files have a seven byte header that ASIC does
not have. If you strip off these 7 bytes and rewrite the file, ASIC
should be able to process the file.
See also:
DEFSEG,BSAVE
Page - 41
BSAVE
Format: BSAVE string1, integer1, integer2
Description:
This statement writes the block of memory beginning at offset
integer1 from the start of the data segment for a length of integer2
bytes to the file specified by string1. This data may be later loaded
by BLOAD. If DEFSEG has been set, it will be used as the data segment,
otherwise, the default ASIC data segment will be used.
Integer2 should be in the range of 1 to 32767.
Example:
DEFSEG = &hexB800
BSAVE "SAVED.DAT" 0 4000
After execution of these statements 4000 bytes at offset 0 bytes from
the start of the override data segment (which in this case happens to
point to the beginning of video memory for a CGA card) will be written
to the file "SAVED.DAT". Assuming a CGA card was present, the current
screen would be saved to disk, assuming you are not in graphics mode.
Comments:
If ASIC detects an error executing this command, it will set the
system ERROR variable. These error codes are listed in the Error
Messages Chapter of the ASIC Manual.
See also:
DEFSEG,BLOAD
Page - 42
CALL
Format: CALL (string1,string2)
Description:
This function can be used to load and execute other programs
compiled with ASIC or another compiler. String1 represents the name of
the program to execute. String2 contains any arguments to be passed to
the program (it may be NULL, ie ""). If an error occurs when ASIC
attempts to call the program, it will set the system ERROR variable to
255. Otherwise, the ERROR variable will be set to the value of the
return code of the called program (which is 0 unless the called program
specifies otherwise).
Example:
CALL ("MYPROG.COM","")
REM other code follows
This statement would cause ASIC to load and execute the program
"MYPROG.COM". No arguments will be passed to the program. When MYPROG
terminates, the calling program will regain control on the line
following the call, in this case the "REM" statement.
Example 2:
CALL ("COMMAND.COM"," /C WP.BAT")
In this example, a ".BAT" type file is executed called "WP.BAT". To run
".BAT" files, it is necessary to load a copy of COMMAND.COM as shown
above (COMMAND.COM contains the DOS code required to load and execute
".BAT" files). Using this format, you can also run some "built in" DOS
commands such as DIR or SORT. Using CALL with this format, is similar
to using the GWBASIC/BASICA SHELL command.
Comments:
String1 must contain the FULL pathname of the program
(ie,"\directory\progname.COM") only if the program is NOT in the current
directory. You must include the file extension on the file name (for
example, use "MYPROG.COM" instead of just "MYPROG", or use "MYPROG.EXE"
instead of "MYPROG").
If you wish to pass arguments to the program build it as follows:
YOURPARM$ = "arguments"
N = LEN(YOURPARM$)
A$ = CHR$(N)
A$ = A$ + YOURPARM$
B$ = CHR$(13)
A$ = A$ + B$
CALL "progname" a$
Page - 43
CALL (Continued)
The above creates an argument list according to the strict DOS
calling rules, however, you can just create the arguments in a string,
and precede them with a leading space. This will work for arguments up
to 32 characters in length (space character is ASCII 32). You might
want to try this short cut first, and only resort to the full formal
approach if you have problems with it, or need to specify longer
arguments:
CALL "progname" " arguments"
CAUTION:
You may use the debugger with programs which contain "CALL"
statements. However, the programs you call should not themselves
contain debugging code. For example, if A.ASI calls B.ASI, then make
sure you compile B.ASI with the "Debugging Code" option OFF before you
try to debug program A.ASI. Failure to do so will cause the debugger to
behave erratically. This also applies to programs you write using other
compilers, since they also use the same interrupt as ASIC (INT 3).
See also:
RUN,COMMAND$
CHDIR
Format: CHDIR string1
Description:
This statement will change the current directory to that specified
in string1. If an error occurs when ASIC executes this command, it will
set the System ERROR variable. A list of possible error codes is listed
in the Error Messages Chapter of the ASIC Manual.
Example:
CHDIR "\DOS"
IF ERROR = 0 THEN NOERROR:
If Drive "C" was the current drive, then this statement would change the
current directory to "C:\DOS".
CHDIR "C:\DOS"
This statement would change the current directory on drive C to "C:\DOS"
whether or not drive C is the current drive. It would NOT change the
default drive to "C". Note that DOS retains a current directory for
each disk drive on your computer.
See also:
MKDIR, RMDIR
Page - 44
CHR$
Format: string1 = CHR$(integer1)
Description:
This function converts an integer in the range of 0-255 to an
ASCII character, and stores in string1.
Example:
A$ = CHR$(49)
After execution of this statement, "A$" will contain "1", since "1" is
represented by ASCII 49.
Comments:
If integer1 is outside the range 0-255, then the least
significant byte of integer 1 is converted to string1.
CLOSE
Format: CLOSE integer1
Description:
This function closes the file number identified by integer1. If an
error is returned by DOS, the system variable "ERROR" will be > 0.
Example:
CLOSE 1
IF ERROR > 0 THEN CHECKERROR:
After successful execution of the CLOSE statement, the file previously
opened as file 1 will be closed. If an error is returned by DOS, the
ERROR variable will be set by ASIC to a non-zero value.
Comments:
IF YOU FAIL TO CLOSE AN OPEN FILE (WHICH WAS OPENED FOR WRITING),
YOU MAY LOSE DATA, SINCE FILE I/O IS BUFFERED, AND THE LAST BUFFER MAY
NOT HAVE BEEN FLUSHED.
Also, integer1 may only be a constant with the value of 1-3.
See Also:
OPEN,PRINT#,INPUT#
Page - 45
CLS
Format: CLS
Description:
This function clears the screen.
Example:
CLS
After execution of the above statement, the screen will be cleared.
CODE
Format: CODE integer1[,integer2...integerN]
Description:
This function may be used to insert machine language code directly
into your program. Integer1 through integerN should be constants in the
range of 0-255. At least one integer must be specified, however, ASIC
will allow up to 30.
Example:
CODE 205,5
This statement represent the machine code generated from the assembly
language statement "INT 5". INT 5 is the BIOS routine which will print
the screen to the printer. After execution of these statements in your
program, the current screen contents would be printed on your printer.
Comments:
THIS STATEMENT IS INTENDED FOR ADVANCED PROGRAMMERS. THIS
STATEMENT IS VERY POWERFUL, AND IF YOU DON'T UNDERSTAND MACHINE LANGUAGE
YOU COULD EASILY CRASH YOUR PROGRAM.
When you use this statement, be sure to save the contents of the
following 8088 registers if you plan to modify them, and restore them
before returning to ASIC. Otherwise the results may be unpredictable.
Registers: DS/CS/ES/SS. Also, make sure you clean up the stack before
you return (ie, if you push a value to the stack, make sure you pop it
before you return to ASIC) Failure to do so, will almost certainly
cause your program to crash.
Page - 46
COLOR
Format: COLOR integer1,integer2
Description:
This function is used to set the foreground and background screen
colors. The foreground color is specified in integer1, the background
color in integer2.
Valid Colors: Foreground Background
---------- ----------
Black 0 0
Blue 1 1
Green 2 2
Cyan 3 3
Red 4 4
Magenta 5 5
Brown 6 6
White 7 7
Dark Gray 8
Light Blue 9
Light Green 10
Light Cyan 11
Light Red 12
Light Magenta 13
Yellow 14
Bright White 15
Note: Colors 8-15 when specified for background color
result in blinking text.
Example:
COLOR 4,8
After execution of this statement, future characters written to the
screen will be Blinking Red on a Black Background.
Page - 47
COMMAND$
Format: string1 = COMMAND$
Description:
This statements retrieves any command line arguments that were
entered and stores them in string1.
Example:
If your program was invoked with: MYPROG XXX
And if your program MYPROG.ASI contained the following:
A$=COMMAND$
PRINT A$
After execution of these statements, the screen would display " XXX".
Comments:
In the integrated environment, you can specify command line
arguments on the "Run" Menu.
This statement is an extension over BASICA/GWBASIC.
Page - 48
COMSTAT
Format: integer1 = COMSTAT (integer2)
Description:
This statement returns the status of a com port. Integer2 should
contain "0" for COM1, or "1" for COM2. The status of that COM port is
returned in integer1. Each bit in integer1 represents a different piece
of information. These are described in the table below. Note that you
may test if a bit is on/off using the ZBIT command.
Example:
PORTSTAT = COMSTAT (0)
DATAREADY = ZBIT(8,PORTSTAT)
IF DATAREADY = 1 THEN GORECEIVE:
These statements do the following. The first retrieves the status of
COM1 to the variable PORTSTAT. The second checks to see if bit 8 is on,
DATAREADY will contain 1 if so, otherwise it will contain 0. Since Bit
8 is used to determine if data is waiting to be received from the port,
if DATAREADY = 1 then the program will transfer to the label GORECEIVE:
which would contain code to RECEIVE data from the port.
Comments:
Status Codes Returned by COMSTAT (Meaning when set to 1)
Bit 0 Delta clear-to-send
1 Delta data-set-ready
2 Trailing-edge ring detector
3 Delta receive line signal detect
4 Clear-to-send
5 Data-set-ready
6 Ring Indicator
7 Received line signal detect
8 Data Ready
9 Overrun error
10 Parity error
11 Framing error
12 Break-detect error
13 Transfer holding register empty
14 Transfer shift-register empty
15 Time-out error
See also:
OPENCOM,SEND,RECEIVE
Page - 49
CSRLIN
Format: integer1 = CSRLIN
Description:
This function returns row of the cursor.
Example:
LOCATE 10,20
A = CSRLIN
The locate command will have positioned the cursor in row 10, column 20.
After execution of the CSRLIN statement, "A" will contain the value of
10.
See also:
POS
Page - 50
DATA
Format: DATA constant1[,constant2,...,constantn]
Description:
This statement is used store integer and string constants in memory
for later retrieval by READ statements. At least one integer or string
constant must be specified, although multiples of each type are
permitted.
Example:
DATA 1,"APPLE",2&,"ORANGES"
READ A
READ A$
READ B&
READ B$
The above statements are equivalent of entering the following code:
A=1
A$="APPLE"
B&=2&
B$="ORANGES"
Comments:
All DATA Statements must be placed at the beginning of the program,
before all other statement types, except DIM or REM statements (or blank
lines). DIM statements, if specified, must precede all other statements
including DATA statements except REM statements (or blank lines). As
long as you follow these rules, you may specify an unlimited number of
DATA statements.
GWBASIC/BASICA does not require quotes around string constants in
some instances. ASIC always requires quotes around string constants.
See also:
READ,RESTORE
Page - 51
DATE$
Format: string1 = DATE$
Description:
This function returns the value of the system date in the format of
"MM-DD-YYYY".
Example:
A$=DATE$
PRINT A$
After executing these statements, the date stored in the PC
System Clock will be displayed on the screen.
Comments:
Note: if the date printed is wrong, you have probably not set the
system clock. Most older XTs and PCs do not have a battery to preserve
the DATE and TIME in the system clock, so you have to set them each time
you power up the PC. Most ATs and newer PCs have a battery backup, so
that the date is preserved for you.
Unlike GWBASIC/BASICA, you cannot set the system date with DATE$,
however, you can set the system date from DOS by typing DATE.
See also:
TIME$, TIMER
DEFSEG
Format: DEFSEG = integer1
This function is used the alter the default data segment used when
peeking and poking data with PEEK and POKE statements. DEFSEG, PEEK,
and especially POKE are not recommended for beginners. If integer1 =-1,
then the data segment address is set back to the ASIC default data
segment address.
Example:
DEFSEG = -1
Execution of the above statement would reset the default data segment to
the default ASIC data segment.
See also:
PEEK, POKE, BLOAD, BSAVE
Page - 52
DIM
Format: DIM variable(integer1)
Description:
This statement will create one dimensional arrays. An integer
variable name must be specified in variable. Integer 1 contains the
number of elements in the array.
Example:
DIM A(10)
DIM A&(20)
In this example an array of 10 normal integer variables is defined, and
an array of 20 long integer variables is defined.
Comments:
On the DIM statement, integer1 may only be a constant. Also, DIM
statements must appear before all other statement types in the program
except REM statements (or blank lines).
END
Format: END [(integer1)]
Description:
This statement causes your program to terminate and return to DOS,
optionally setting a return code. Integer1 may be optionally specified
to set the return code. If omitted, ASIC uses a return code of zero by
default.
Example:
END
In this example, the program will terminate and return to DOS with a
return code of zero.
END (20)
In this example, the program will terminate and return to DOS with a
return code of "20".
Comments:
The optional return code is an extension over GWBASIC/BASICA.
Page - 53
ENVIRON$
Format: string1 = ENVIRON$(integer1)
Description:
This statement will retrieve DOS environment strings. Integer1
identifies which string to retrieve. If found, the string is placed in
string1. If not found, a NULL string (length=0) is stored in string1.
Example:
FOR I=1 TO 5
A$=ENVIRON$(1)
PRINT A$
NEXT I
The above example will retrieve the first five DOS environment strings
and display them.
Comments:
If the requested DOS environment string entry is greater than 80
characters in length, ASIC will truncate it at 80 characters.
Environment strings may be set in DOS using the SET command.
Environment strings are one way of passing information to your program.
Refer to your MS DOS Manual for more information.
Page - 54
FILEPOS
Format: integer1 = FILEPOS (integer2,integer3) <--Format 1
integer1 = FILEPOS (integer2,EOF) <--Format 2
integer1 = FILEPOS (integer2,CURRENT) <--Format 3
Description:
This statement is used to set or retrieve the read/write position
for files opened in Random mode. In all three formats, integer2 is the
file number of the file. This file number must have been previously
opened for Random mode by the OPEN statement. Format 1 is used to set
the current read/write position of the file specified by integer2.
Integer3 should be the offset (in bytes) from the start of the file.
Format 2 is used to set a read/write position of a random file to the
end of the file. Format 3 is used to retrieve the current read/write
position (as a byte offset from the beginning of the file) of the file.
In all cases, if an error occurs, the system ERROR variable will be set.
A list of these codes is contained in the Error Codes Chapter of the
ASIC Manual. If no error occurs, then integer1 will be set to the
current read/write position of the file.
Example 1:
A&=FILEPOS(1, 100)
This example assumes that file 1 was previously opened for RANDOM I/O
using the OPEN statement. After execution of this statement, the
read/write position of file number 1 will be set to 100. Subsequent
PRINT # statements would write to the file starting at position 101.
Example 2:
A&=FILEPOS(1,EOF)
This example assumes that file 1 was previously opened for RANDOM I/O
using the OPEN statement. After execution of this statement, the
read/write position of file number 1 will be set to the end of the file.
Subsequent PRINT # operations to this file will result in data being
appended to this file.
Example 3:
A&=FILEPOS(1,CURRENT)
This example assumes that file 1 was previously opened for RANDOM I/O
using the OPEN statement. After execution of this statement, the
current read/write position of file number 1 will retrieved and stored
in integer1. The read/write position of file number 1 will NOT be
altered after execution of this statement.
Page - 55
FILEPOS (Continued)
Comments:
If you wish to use this command with files larger than 32767 bytes,
you should use long integers with this statement. If you set the
read/write position past the physical end of file and attempt to read
from the file, you will receive an error on the INPUT# command. If you
set the read/write position past the end of file and issue a PRINT#
command, the data will be correctly written at the position you
specified.
See also:
OPEN, INPUT#, PRINT#, CLOSE
Page - 56
FIND
Format: string1=FIND FIRST (string2,integer1)
string1=FIND CONTINUE
Description:
The FIND command is used to search the current file directory for
file(s) which match a search string. This command has two versions.
FIND FIRST must be used to establish a new search and retrieve the first
matching file name. Thereafter, the FIND CONTINUE will retrieve
additional file names which match the search string. When performing
the FIND FIRST, string2 should contain the full or partial file name to
be searched for. This string can be up to 8 alphanumeric characters
optionally followed by a period and up to 3 alphanumeric characters for
the file extension. Standard DOS wild cards "*" and "?" may be included
in the search string. Integer1 is used to specify a file attribute. If
integer1 is "0", then all normal files in the directory will be
searched. (A normal file is one in which the hidden, system, volume
label, or directory attribute bit is NOT set). Setting various bits
(see table below) of integer1 ON will expand the search to include
normal files, plus those whose attributes have been specified in
integer1. If a matching file name is found, then it will be stored in
string1. If an error occurs, then the system ERROR variable will be
set. A list of ERROR codes is contained in the ERROR code chapter of
the ASIC Manual. After the initial FIND FIRST has been performed, you
may search for additional files which match the search string and
attribute by issuing a FIND CONTINUE statement.
Search Attributes bits (integer1)
--------------------------------
BIT
0 Not Used
1 Hidden
2 System
3 Volume Label
4 Subdirectory
5-7 Not Used
Note that these attributes can all be specified simultaneously. For
example, to specify both hidden and system, use an attribute value of
&bin00000110 (in binary) or 6 (in decimal).
Page - 57
FIND (Continued)
Example:
SEARCH$="*.ASI"
ATTRIB=0
FILENAME$=FIND FIRST (SEARCH$,ATTRIB)
IF ERROR>0 THEN DONE:
PRINT A$
LOOP:FILENAME$=FIND CONTINUE
IF ERROR>0 THEN DONE:
PRINT A$
GOTO LOOP
DONE: PRINT "ALL MATCHING FILES DISPLAYED"
END
After execution of the above statements, all of the files with a file
extension of ".ASI" in the current directory will be displayed on the
screen.
Comments:
If you execute a FIND CONTINUE without executing a FIND FIRST, then
the results are unpredictable. Additional information is retrieved by
the FIND command besides the file name. Advanced programmers can also
find additional information using the PEEK command starting at offset
149 (from the default ASIC data segment). Do not modify this data. If
you do so, the results are unpredictable.
Additional File Information
---------------------------
Address Size (bytes) Description
149 1 File Attribute
150 2 File Time Stamp
152 2 File Date Stamp
154 4 File Size (bytes)
See also:
NAME, KILL, GETDIR, CHDIR, MKDIR, RMDIR
Page - 58
FOR/NEXT
Format: FOR integer1 = integer2 to integer3
NEXT integer1
Description:
These two statements are used to create a loop, so that you can
execute a portion of your program a certain number of times. All of the
code between the FOR and the NEXT statement will be executed a certain
number of times, but at least once. The actual number of times the loop
executes is dependent on integer1/integer2/integer3.
When the FOR statement is encountered in your program, integer1 is
assigned the value of integer2. Then the statements up to the matching
NEXT statement is executed one time. Then, 1 is added to integer1, and
integer1 is compared to integer3. If integer1 is greater than integer3
then the control passes to the statement following NEXT. Otherwise, the
program loops back up to the statement following the FOR statement.
Example:
FOR I = 1 TO 2
FOR J = 3 TO 5
PRINT I;
PRINT J
NEXT J
NEXT I
PRINT "AFTER THE LOOP";
PRINT I;
PRINT J;
Execution of this section of code would result in the following
printout:
1 3
1 4
1 5
2 3
2 4
2 5
AFTER THE LOOP 3 6
Comments:
Unlike BASICA/GWBASIC, ASIC FOR/NEXT loops execute at least 1 time.
For example, the value "HELLO" will be printed in the following example.
It wouldn't have been in BASICA/GWBASIC.
FOR I = 1 TO 0
PRINT "HELLO"
NEXT I
Page - 59
FOR/NEXT (Continued)
Unlike GWBASIC/BASICA, arrays may be used for integer1 and
integer2. However, if integer3 is an array, element zero will be used,
regardless of the subscript you specify.
ASIC will allow you to modify the value of integer3, while
GWBASIC/BASICA ignores changes.
J=1
FOR I=1 TO J
J=2
NEXT I
The above loop will execute one time in GWBASIC/BASICA, but it will
execute two times in ASIC.
GETDIR
Format: string1=GETDIR (integer1)
Description:
This statement is used to retrieve the current DOS directory.
Integer1 should be set to "0" to obtain the directory for the current
drive, "1" for the "A" drive, "2" for the "B" drive, etc. If the
statement is unsuccessful, the system ERROR variable will be set. A
complete list of ERROR codes is contained in the Error Code Chapter of
the ASIC Manual. The directory string will be stored in string1. The
directory string will not contain the drive letter, or the first "\".
Thus, if the current directory on the specified drive was "C:\ASIC",
then GETDIR would return "ASIC". If the current directory was the root
(eg, "C:\"), then GETDIR would return a NULL string ("").
Example:
A$=GETDIR(0)
After execution of this statement, the variable A$ will contain the name
of current directory on the current disk drive.
See also:
FIND, MDKIR, RMDIR, CHDIR
Page - 60
GOSUB
Format: GOSUB label1
Description:
This statement "calls" a subroutine called "label1". This
subroutine must contain a "RETURN". After the subroutine is executed,
control is returned to the next statement following the GOSUB.
Example:
GOSUB PRINTIT:
PRINT "All Done!"
END
PRINTIT: PRINT "It"
RETURN
After execution of this code the screen would contain:
It
All Done!
GOTO
Format: GOTO label1
Description:
This statement transfers program execution to the statement
identified by label1.
Example:
GOTO SKIPIT:
PRINT "YOU'LL NEVER GET HERE"
SKIPIT: PRINT "ALL DONE!"
After execution of this code, the screen will appear as follows:
ALL DONE!
Note that the first print statement never executes because of the GOTO.
Page - 61
IF/THEN/ELSE/ENDIF
Format: IF condition THEN label1 <--Format 1
IF condition THEN label1 ELSE label2 <--Format 2
IF condition THEN <--Format 3
<zero or more ASIC statements>
ENDIF
IF condition THEN <--Format 4
<zero or more ASIC statements>
ELSE
<zero or more ASIC statements>
ENDIF
Description:
This statement is used to conditionally transfer to a different
location in the program. The operand "condition" is one of the
following:
integer1 > integer2
string1 > string2
integer1 = integer2
string1 = string2
integer1 < integer2
string1 < string2
Format 1--If "condition" is true, control is transferred to label1.
Otherwise the program continues at the next statement.
Format 2--If "condition" is true, control is transferred to label1,
otherwise the program branches to label2 and continues execution from
there.
Format 3--If "condition" is true, the program will continue execution at
the next statement. If the condition is false, the program will branch
to the statement following the next ENDIF statement encountered.
Format 4--If "condition" is true, program will continue execution at the
next statement up to the next ELSE statement encountered, at which point
it will branch to the statement following the next ENDIF statement
encountered. If "condition" is false, the program will branch to the
next ELSE statement and resume execution at that statement.
Example 1:
IF A > 0 THEN APLUS:
In this example, if A is greater than zero, the program jumps to the
label called "APLUS:".
Page - 62
IF/THEN/ELSE/ENDIF (Continued)
Example 2:
IF A$="YES" THEN TRUE: ELSE FALSE:
In this example, if A$ contains the string "YES", the program jumps to
the label called "TRUE:", otherwise the program transfers to label
"FALSE:"
Example 3:
OPEN "I",1,"TEST.DAT"
IF ERROR>0 THEN
PRINT "ERROR OPENING FILE";
PRINT ERROR
END
ENDIF
REM rest of program follows
.
.
In this example, if there is an error opening file "TEST.DAT", the
program will print an error message and terminate. Otherwise control
will fall through to the REM statement and the program will continue.
Example 4:
PRINT "ENTER A NUMBER";
INPUT NUMBER
IF NUMBER > 100 THEN
PRINT "THAT'S A BIG NUMBER"
ELSE
PRINT "THAT'S A SMALL NUMBER"
ENDIF
Comments:
Formats 3 and 4 are BLOCK IF formats. You can nest BLOCK IF
statements up to 25 levels deep. The example below is shown three
levels deep.
IF A=1 THEN <-Level 1
IF B=2 THEN <-Level 2
IF C=3 THEN <-Level 3
PRINT "C=3, B=2, AND A=1"
ELSE
PRINT "C<>3, B=2, AND A=1" <-ELSE for Level 3
ENDIF <-ENDIF for Level 3
ENDIF <-ENDIF for Level 2
ENDIF <-ENDIF for Level 1
It's a good idea to indent your IFs, ELSEs and ENDIFs as shown
above. Otherwise matching IFs up with matching ENDIFs and ELSEs can
become very confusing.
Page - 63
INKEY$
Format: string1 = INKEY$
Description:
Used to retrieve keystrokes from the keyboard buffer. If a
character is waiting in the buffer, string1 will be set to the value of
that character, and that character will be removed from the keyboard
buffer. If the buffer is empty, string1 will be set to a value of ""
(that is, a null string with a length of 0). If an extended key is
pressed (for example the function keys F1 through F10), the system
variable EXTENDED will be set to 1, otherwise it will contain 0.
Example:
LOOP: X$=INKEY$
IF X$="" THEN LOOP:
The above code will cause the program to loop until a key is pressed.
Comment:
ASIC provides an extension here over BASICA/GWBASIC. The EXTENDED
system variable will allow you to detect special keys as mentioned
above. To do so requires an understanding of keyboard scan codes, which
is beyond the scope of the ASIC Manual. For more information I would
suggest Peter Norton's Programmer Guide to the IBM PC (Microsoft Press).
INP
Format: integer1 = INP (integer2)
Description:
This statement reads a byte from port integer2 and stores the
result in integer1.
Example:
A=INP(513)
A=ZBIT(4,A)
IF A=1 THEN TRIGGERPRESSED:
The above code will test the joystick port to see if the trigger is
being pressed on joystick 1. You need a game card and joystick for this
to work.
See also:
OUT
Page - 64
INPUT
Format: INPUT variable1
Description:
This statement will retrieve a line of text terminated from the
input buffer and stores it in variable1. ASIC will first issue the
prompt "?". It will then wait until the user enters a string or integer
and presses the <return> or <enter> key. The type of data ASIC will
expect is dependent on the type of variable1 (integer or string). If an
integer is being entered, ASIC will edit the input for validity as an
integer, and if the edit fails will issue another "?" to the user, and
will wait for the number to be retyped. Only when a valid integer has
been entered will variable1 be updated, and only then will control
return to your ASIC program.
Example:
PRINT "Enter a String";
INPUT A$
ASIC will issue the prompt:
Enter a String?
It will then wait until you enter a string or press enter. If you
pressed enter with no characters A$ would contain "" (ie its length
would equal 0), otherwise A$ would contain the string entered.
Example:
INPUT I
In this example ASIC will issue the prompt:
?
ASIC will then wait for you to enter a valid number. If you enter an
invalid number, say "x", ASIC will reissue the "?" prompt and wait for
you to retype your input. Once the input has been edited by ASIC, "I"
would contain the number entered.
See Also:
INKEY$
Page - 65
INPUT#
Format: INPUT# integer1, integer1 <-Format 1
INPUT# integer1, string1 <-Format 2
INPUT# integer1, string1 CRLF <-Format 3
INPUT# integer1, string1 NONULL <-Format 4
INPUT# integer1, string1 BYTE <-Format 5
Description:
This statement will read a variable from a file identified by file
number integer1. It will be stored in integer1/string1. If an error
occurs during a read, the system variable ERROR will be set to a non-
zero value. The possible errors are listed in the error messages
section the of the ASIC Manual. If you read a file past its end, the
contents of variable1 are undefined.
Five formats of this statement are provided to provide greater
flexibility in reading files written by ASIC and non-ASIC programs. The
five formats are summarized below:
Format 1 -- Read integers from a file previously written by ASIC.
Format 2 -- Read strings from a file previously written by ASIC.
Format 3 -- Read strings from a non-ASIC file. Assumes the strings
(CRLF) will be terminated by a CR/LF (carriage return/linefeed).
Note that ASIC still considers a NULL character, if
encountered, as an end of string character. Also ASIC
terminates the string if 80 characters are read before
encountering a CR/LF pair.
Format 4 -- Read strings from a file until 80 characters or the end
(NONULL) of the file is reached. Note that ASIC still considers a
NULL character, if encountered, as an end of string
character.
Format 5 -- Reads a single byte from a file and stores it in string1.
(BYTE) If ASIC has read a NULL byte, the string will be set to
NULL and its length will be 0.
Example 1:
OPEN "I",1,"TEMP.DAT"
INPUT#1, A$
IF ERROR=99 THEN ENDOFFILE:
In this example, a string will be read from file "TEMP.DAT", and it will
be stored in A$. The system ERROR variable is then checked to see if
End of file was reached. Note, other ERRORS could also be returned by
INPUT#, besides error code 99. Refer to the error messages section for
more information.
Page - 66
INPUT# (Continued)
Example 2:
OPEN "I",1,"TEMP.DAT"
INPUT#1, A$ NONULL
IF ERROR=99 THEN ENDOFFILE:
In this example, ASIC will read 80 characters from the file "TEMP.DAT",
or up until the next NULL character in the file, which ever comes first.
Example 3:
OPEN "I",1,"CONFIG.DAT"
INPUT#1, A$ BYTE
IF ERROR=99 THEN ENDOFFILE:
In this example, ASIC will read a single character from the file
"CONFIG.DAT", and place it in the variable A$.
Example 4:
OPEN "I",1,"TEST.DAT"
INPUT#1, A
IF ERROR=99 THEN ENDOFFILE:
In this example, ASIC will read an integer value from the file
"TEST.DAT", and place it in the integer variable "A".
Example 5:
OPEN "I",1,"ASCII.DAT"
OPEN "O",2,"ASCII.NEW"
CR$=CHR$(13)
LF$=CHR$(10)
CRLF$=CR$+LF$
READMORE:
INPUT #1, A$ CRLF
IF ERROR=96 THEN WRITE:
IF ERROR>0 THEN ENDOFFILE:
WRITEWITHCRLF:
PRINT #2,A$ NONULL
PRINT #2,CRLF$ NONULL
GOTO READMORE:
WRITE:
PRINT #2, A$ NONULL
GOTO READMORE:
ENDOFFILE:
CLOSE 1
CLOSE 2
This example copies file ASCII.DAT to file ASCII.NEW. Note: Even
though ASIC can only handle 80 character strings, this example shows
that by checking the ERROR variable for a value of 96, it is possible to
read the file in up-to-80-character chunks and reassemble the strings in
their original forms in the new file. Also note that ASIC will still
treat any NULL characters in the file as an end of string character.
Page - 67
INPUT# (Continued)
Comments:
Note that integer1 must be a constant in the range of 1-3. It
identifies a file by file number which must have previously been opened
by an OPEN command for modes INPUT or RANDOM.
ASIC assumes that integers will be stored in files in 2-byte binary
format, which is the format ASIC writes integers. Consequently, If a
file contained a string "123", but you told ASIC to read integer "X",
then ASIC would read two bytes from the file and interpret "12" as two
binary bytes that it would then combine and store as "X". "X" would
contain the integer value 12849. Thus to read an integer correctly, you
will have had to previously written it with an ASIC program.
See Also:
OPEN, CLOSE, PRINT#, FILEPOS
INSTR
Format: integer1 = INSTR (string1,string2)
Description:
This statement is used to determine if a given substring exists
within a string, and if so, the character position at which the
substring first appears in the string. String1 is the string to be
searched. String2 contains the substring to find within string1. The
character position of string2 within string1 is returned in integer1.
If the string is not found then integer1 is set to zero.
Example 1:
A=INSTR("THE QUICK BROWN FOX","QUICK")
After execution of this statement, variable "A" will contain the value
5, which is the offset of the string "QUICK" within the string "THE
QUICK BROWN FOX".
B=INSTR("FOX","HEN")
After the execution of this statement, variable "B" will contain 0,
since the string "HEN" is not found within the string "FOX".
See also:
LEFT$, RIGHT$, MID$, LEN
Page - 68
INT86
Format: INT86(integer1,AX,BX,CX,DX,DI,SI,BP,DS,ES)
Description:
This statement is used to call a DOS, BIOS, or custom-written
Interrupt. Integer1 must be a constant, and should identify the number
of the interrupt to be called. The fields following integer1 represent
the CPU registers. For example, ASIC will move the value from the ASIC
variable "AX" to the CPU register "AX" prior to performing the interrupt
call. After the call, ASIC will move the value from the CPU register
"AX" to the ASIC variable "AX". Your ASIC program can then use this
"AX" variable just like any other integer variable in the rest of the
program. Each of the registers listed (AX,BX,CX,DX,DI,SI,BP,DS,ES) must
be included on the INT86 statement in the same order as shown in the
Format statement above. The exception to this rule, is that you can
substitute "NA" for any register you do not need for the call. The BP
register may be used to pass values to the INT86 call, however, unlike
all of the other registers, ASIC does not return the value of the BP
register following the INT86 call.
Example 1:
INT86(5,NA,NA,NA,NA,NA,NA,NA,NA,NA)
The above example shows the code to perform a screen print to the
printer. This example will call INT 5 (BIOS Print Screen Interrupt),
pass no parameters to the call, and receive no return values from the
call.
Example 2:
AX=&hex3600
DX=0
INT86(&hex21,AX,BX,CX,DX,NA,NA,NA,NA,NA)
PRINT "Default Drive has:"
PRINT
PRINT "Sectors/Cluster";
PRINT AX
PRINT "Available Cluster Count";
PRINT BX
PRINT "Bytes/Sector";
PRINT CX
PRINT "Total Clusters";
PRINT DX
Page - 69
INT86 (Continued)
This example show a more complex call to DOS to find out free disk space
information for the current drive. DOS Interrupt 21 (hex) function 36
(hex) is used to retrieve this information. The AX register is used to
pass the function number. The DX register is used to select the disk
drive (0=the default disk drive). Note that the BX and CX registers
were included on the call. No parameters are being passed to the call
in these registers, however, we'll be receiving information back from
DOS in them, so they need to be on the INT86 statement. Since the
SI,DI,BP,DS, and ES registers are not needed by the call, they have been
substituted with "NA" which you can think of as meaning "Not Applicable"
to this call. After the call, the example program will display
information about the default disk drive.
Comments:
This statement is intended for advanced programmers. To use it
properly, you must have some knowledge of assembler language, or at
least about the CPU registers in the IBM PC. You also need a DOS or
BIOS reference manual to identify which registers to pass to each
interrupt, and to identify the values to place in those registers.
One register was required for ASIC housekeeping after the INT86 call.
This is why the BP register is unavailable to receive return values from
calls. The BP register was chosen, because none of the DOS or BIOS
Interrupts use this register to return values. If you write your own
interrupts and want to call them from an ASIC program, remember that you
can pass the BP register to the interrupt, but the ASIC "BP" variable
will not be updated following the interrupt.
If a register is not needed for the call, specify "NA" instead of the
register name. ASIC does not generate any code for "NA" registers, and
this will reduce the size of your program.
Page - 70
KILL
Format: KILL string1
Description:
This statement is used to delete a file from disk. It is similar
to the DOS ERASE Statement. Specify the file to delete in string1. You
can specify the full path to the file, or just the file name if it is in
the current directory. If an error occurs (eg, File not found), then
ASIC will set the System ERROR variable. A list of codes returned by
KILL is listed in the ERROR Messages Chapter of the ASIC Manual.
Example:
KILL "TEMP.DAT"
IF ERROR = 0 THEN NOERROR:
REM CHECK ERROR CODES HERE
After this statement is executed, the file "TEMP.DAT" will have been
erased from the current directory of the current drive, and will no
longer be accessible from DOS or your programs.
LCASE$
Format: string1=LCASE$(string2)
Description:
This statement will convert all of the letters in string2 from
upper case to lower case, and store the result in string1.
Example:
A$=LCASE$("123 Main Street, USA")
After the execution of this statement, the variable A$ will contain the
string "123 main street, usa".
See also:
UCASE$
Page - 71
LEFT$
Format: string1=LEFT$(string2,integer1)
Description:
This statement will copy integer1 characters from the left of
string2 to string1.
Example:
A$=LEFT$("RED RIDING HOOD",3)
After the execution of the above statement, the variable A$ will contain
the string "RED".
See also:
MID$, RIGHT$
LEN
Format: integer1 = LEN (string1)
Description:
This statement returns the length (number of characters) of a
string, and stores the length in integer1.
Example:
A$="abc"
LENGTH1 = LEN(A$)
After execution of these statements, LENGTH1 would contain 3.
Page - 72
LOCATE
Format: LOCATE row,column
Description:
This statement is used to position the cursor to a row and column.
Row and Column should be integers. Row has the range 0-24, Column has
the range 0-79. This function does not perform edits on the ranges of
row and column. Consequently using this function with values outside
these ranges will have unpredictable results.
Example:
LOCATE 10,20
PRINT "HELLO"
After execution of these statements, the message "HELLO" will appear
beginning at row 10, column 20.
LPRINT
Format: LPRINT printobject [;]
Description:
This statement is used to send the contents of printobject to an
attached printer. "printobject" can be any valid ASIC datatype:
integer constant, integer number, string constant, string variable, and
also array elements. Optionally, a ";" can be included with this
statement to suppress a carriage return/line feed which ASIC normally
also sends to the printer following each LPRINT. This can be used to
string several printobjects together on a single print line.
Example:
A=12345
LPRINT "The value of A is: ";
LPRINT A
After execution of these statements the printer would print:
The value of A is: 12345
Comments:
Note that if the printer is not "online" that DOS will issue a
message to "Abort, Retry, or Ignore". This could overwrite a portion of
the program display, unless not planned for.
Note also, that some printers do not begin printing until they
receive a carriage return/line feed sequence.
Page - 73
LTRIM$
Format: string1=LTRIM$(string2)
Description:
This statement will remove all leading spaces from string2 and
store the result in string1.
Example:
A$=" XYZ"
A$=LTRIM$(A$)
After execution of these statements, the variable A$ will contain the
string "XYZ" with no leading spaces.
See also:
RTRIM$
MID$
Format: string1 = MID$(string2,integer1,integer2)
Description:
This statement is used to extract a substring from string2
beginning at position integer1 within string2 and continuing for
integer2 bytes. This value is then stored in string1.
Example:
A$="THE QUICK BROWN FOX"
B$=MID$(A$,1,4)
C$=MID$(A$,11,9)
D$=B$ + C$
After execution of these statements, the contents of A$ will be
unchanged. The contents of B$ will be "THE ". The contents of C$ will
be "BROWN FOX", and the contents of D$ will be "THE BROWN FOX".
See also:
LEFT$, RIGHT$
Page - 74
MKDIR
Format: MKDIR string1
Description:
This statement is used to create a new DOS directory. Specify the
directory to create in string1. If ASIC is unable to create the
directory, it will set the System ERROR variable. A list of ERROR codes
may be found is the Error Messages Chapter of the ASIC Manual.
Example:
MKDIR "WORK"
IF ERROR = 0 THEN NOERROR:
This code would create a directory called "WORK" under the current
directory of the current drive.
Example 2:
MKDIR "C:\WORK"
This code would create a directory called "WORK" under the root
directory of drive "C".
See also:
CHDIR,RMDIR
MOD
Format: integer1 = integer2 MOD integer3
Description:
This statement will perform modulo division of integer2 by integer3
and store the remainder (instead of the quotient) in integer1.
Example:
A = 8
B = 5
C = A MOD B
After execution of these statements, variable "C" will contain the value
"3" which is the remainder of the division of 8 by 5.
Page - 75
NAME
Format: NAME string1 AS string2
Description:
This statement will allow you to rename a file. String1 should
contain the current file name, and string2 should contain the new name
for the file. If ASIC is unable to rename the file, it will set the
System ERROR variable. A list of ERROR codes is contained in the Error
Messages Chapter of the ASIC Manual.
Example:
NAME "olddata.txt" AS "newdata.txt"
IF ERROR = 0 THEN SUCCESS:
After execution of these statements, file "olddata.txt" will have been
renamed to "newdata.txt"
Comments:
You cannot rename a file to a new disk drive.
OPEN
Format: OPEN string1, integer1, string2
Description:
This statement is used to open a file for input or output. Up to
three files may be open concurrently, these are known as file 1, 2, or
3. You must specify with integer1 which file number you wish to open
this file as. Integer1 may only be a constant. The file mode is
specified in string1. The valid values are "I" for INPUT, "O" for
OUTPUT, "A" for APPEND, and "R" for RANDOM INPUT/OUTPUT. The file name
is specified with string2. Any errors returned from DOS on the OPEN
call will be returned in the system variable "ERROR".
Example:
OPEN "I",3,"INFILE"
IF ERROR > 0 THEN PROCESSERROR:
OPEN "O",1,"A:\NEWFILE.DAT"
IF ERROR > 0 THEN PROCESSERROR:
In this example, two files are opened. File "INFILE" from the current
disk drive and directory will be opened as file number 3 for input. The
file "A:\NEWFILE.DAT" will be opened for output as file number 1. Note
that if "A:\NEWFILE.DAT" previously existed, it contents will be
destroyed in preparation for writing.
See also:
CLOSE, FILEPOS, INPUT#, PRINT#
Page - 76
OPENCOM
Format: OPENCOM(integer1,integer2,integer3,integer4,integer5)
Description:
This statement is used to initialize the serial port. Integer1 is
used to specify the baud rate. Integer2 specifies parity. Integer3
specifies stop bits. Integer4 specifies bytesize, and Integer5
identifies which port to open (see the tables below). OPENCOM does not
check the validity of the values you give it.
(integer1) (integer2)
BAUD RATE PARITY
------+----------- ------+------------
VALUE | DESCRIPTION VALUE | DESCRIPTION
0 | 110 baud 0 | No Parity
1 | 150 baud 1 | Odd Parity
2 | 300 baud 3 | Even Parity
3 | 600 baud
4 | 1200 baud (integer3)
5 | 2400 baud STOP BITS
6 | 4800 baud ------+------------
7 | 9600 baud VALUE | DESCRIPTION
0 | One Stop Bit
1 | Two Stop Bits
(integer4) (integer5)
BYTE SIZE COM PORT
------+------------ ------+------------
VALUE | DESCRIPTION VALUE | DESCRIPTION
2 | 7 Bits 0 | Com1
3 | 8 Bits 1 | Com2
Example:
OPENCOM(2,0,0,3,0)
This statement would open COM1 at 300 baud, No parity, 1 Stop bit, 8 bit
bytesize.
See also:
COMSTAT,RECEIVE,SEND
Page - 77
OUT
Format: OUT (integer1,integer2)
Description:
This statement writes a byte to a port. Integer1 should contain
the port to write to. Integer2 should contain an integer value in the
range of 0-255 to be written to the port.
Example:
OUT 512,0
The above statement would send a byte with the binary value of "0" to
port number 512.
See also:
INP
PEEK
Format: integer1 = PEEK (integer2)
Description:
This statement is used to examine actual memory location values
directly. By default, the ASIC DS address is assumed. However, this
may be overridden with the use of the DEFSEG command. The value of the
byte at address integer2 is stored in integer1.
Example:
DEFSEG = &hexB800
A = PEEK (0)
The above statements will retrieve the first byte of video memory for a
CGA/EGA/VGA card and store it in variable "A".
Comments:
Since the Intel 8088 architecture is segmented in 64k segments,
integer2 is limited to the range of 0-65535.
See also:
DEFSEG, POKE
Page - 78
POINT
Format: integer1 = POINT (integer2,integer3)
Description:
This statement is used to determine the color of a given pixel in
medium and high resolution graphics modes. The row to test is specified
with integer2, the column with integer3. The color of the pixel is
stored in integer1.
Example:
PCOLOR = POINT (10,20)
After execution of this statement, PCOLOR will contain the color of the
pixel in row 10 column 20.
Comments:
No range checking is performed on row and column. If the specified
row or column is outside the valid range for the given graphics mode,
the results are unpredictable.
See also:
PSET, PRESET, SCREEN
Page - 79
POKE
Format: POKE integer1, integer2
Description:
This instruction is used store the byte value integer2 at the
memory address specified by integer1. By default, ASIC uses its default
data segment address, however, this may be overridden with the DEFSEG
statement.
Example:
DEFSEG = &hexB800
POKE 0,1
The above statements will store a byte with the binary value of "1" in
the first byte of video memory for a CGA/EGA/VGA card.
Comments:
This statement is NOT RECOMMENDED FOR BEGINNERS. Directly
overwriting memory locations can be disastrous, unless you know what is
stored at that address. This can cause program "hangs", system crashes,
etc.
Since the Intel 8088 architecture is segmented in 64k segments,
integer2 is limited to the range of 0-65535.
See also:
DEFSEG, PEEK
POS
Format: integer1 = POS (integer2)
Description:
This statement finds the column number of the cursor and stores it
in integer1. integer2 is a dummy argument included only because a dummy
argument is required in BASICA/GWBASIC.
Example:
A = POS(0)
After this statement executes, A will contain the column number of the
cursor.
See also:
CSRLIN
Page - 80
PRESET
Format: PRESET (integer1,integer2)
Description:
This statement is used to set the color of a pixel to the
background color. The row of the pixel is specified in integer1, and the
column is specified in integer2. This statement only works in graphics
modes.
Example:
PRESET (10,20)
The pixel at row 10 column 20 would be set to the background color.
See also:
PSET, SCREEN, POINT
PRINT
Format: PRINT [printobject1 [;]]
Description:
This statement is used to print to the screen. Printing begins at
the current cursor location. Printobject1 is defined as any valid ASIC
data type: integer constant, integer variable, string constant, string
variable, and arrays. The semicolon is optional and is used to tell
ASIC if you want a carriage return/line feed issued. A semicolon at the
end of a PRINT statement will suppress the carriage return/line feed
ASIC normally issues. If no operands are supplied, ASIC will simply
issue a carriage return and line feed.
Example:
A=1000
PRINT "A=";
PRINT A
PRINT
PRINT "DONE!"
After execution of these statements your screen would display:
A= 1000
DONE!
See also:
COLOR, SCREEN, LOCATE
Page - 81
PRINT#
Format: PRINT# constant1, printobject1 [NONULL]
Description:
This statement is used to write integers and strings to disk.
Constant1 identifies the file number that the file was opened as. This
must be a constant with a value of 1, 2 or 3. The file must have been
previously opened with the OPEN command. If printobject1 is a string,
you can also add the optional argument "NONULL", which will cause ASIC
to suppress the trailing NULL character it would normally write to disk.
DOS errors are returned in the system variable "ERROR". A list of these
error codes may be found in the error messages section of the ASIC
Manual. Also, refer to the technical details section of the ASIC Manual
for more information on the format in which ASIC writes the data to
disk.
Example:
PRINT# 1, "HELLO"
IF ERROR = 255 THEN DISKFULL:
PRINT# 1, "WORLD"
IF ERROR = 255 THEN DISKFULL:
After successful execution of the print statements the file identified
by file number 1 would contain "HELLO0WORLD0" . Note that the "0"
following HELLO and WORLD in our example represents the ASCII null
character. Strings in ASIC are always internally terminated with ASCII
null characters. By default, these nulls are also written to disk.
PRINT# 2, "HELLO" NONULL
In this example, the string "HELLO" would be written to file #2, and no
trailing NULL will be written to disk.
PRINT #3, 1234
In this example, the number "1234" would be written to file #3 as two
bytes in Intel binary format (the file would contain the two hexadecimal
bytes: D2 04).
Page - 82
PRINT# (Continued)
Comments:
Note that while ASIC doesn't generate carriage returns and line feeds
for you as it does with the PRINT command, you can write these
characters to disk as follows:
A$=CHR$(13)
B$=CHR$(10)
A$ = A$ + B$
PRINT #1, A$
You might be wondering about the purpose of the NONULL option. ASIC
normally writes trailing NULLs with strings. This is desirable if you
plan to read the file exclusively with other ASIC programs.
However, sometimes you may want to write a string for use by another
program. In this case, the NULL character sometimes confuses the other
program. Specifying the NONULL option will cause ASIC to suppress the
offending NULL character.
What happens if you read a string that is terminated by a Carriage
Return/Line Feed Sequence (such as GWBASIC/BASICA produces)? In this
instance, specify the CRLF option on the INPUT# statement. Then ASIC
will read the string until it finds a CR/LF or until it reads 80
characters, whichever comes first.
See also:
OPEN, CLOSE, INPUT#, FILEPOS
Page - 83
PSET
Format: PSET (integer1,integer2),integer3
Description:
This statement is used to set a pixel to a specified color in
graphics modes. The row is specified in integer1, the column in
integer2, and the color in integer3. Note that no range checking is
performed on integer1 or integer2. A row or column specified outside
the range allowed by the graphics mode in use can result in
unpredictable results.
Example:
PSET (10,20),1
In this example the pixel defined at row 10 and column 20 will be set to
color 1.
See also:
PRESET, SCREEN, POINT
RANDOMIZE
Format: RANDOMIZE
Description:
This statement will cause the seed for the random number
generator to be reseeded using the system timer. This statement should
always precede the first RND statement in your program, unless you want
the same sequence of random numbers generated.
Example:
RANDOMIZE
The above statement would insure that each time your program runs, any
subsequent RND numbers generated would be different.
See also:
RND
Page - 84
READ
Format: READ variable1
Description:
This statement reads a constant from DATA statements into a
variable. Variable1 is either a string or integer type variable.
Example:
DATA 7,"CARGO"
READ A
READ B$
After execution of these statements, "A" will contain 7, and B$ will
contain "CARGO".
Comments:
ASIC does not check to see that the data type on the READ statement
matches the data type on the DATA statement. It is up to the programmer
to insure that the types match. The above example is correct. The DATA
statement contains an integer, then a string. This is the same sequence
in which the DATA is READ (ie, integer, then string). In the above
example, if the read statements were reversed, the contents of A and B$
are undefined. Also note that ASIC does not check to see that you don't
read past the end of the DATA you specified. In the above example, if
you had a third READ statement that contained "READ C$", then C$ would
contain random garbage, since you read three values, but only provided
data for two.
See also:
DATA,RESTORE
Page - 85
RECEIVE
Format: variable1 = RECEIVE(integer2)
Description:
This statement will read a byte from the specified serial port.
Integer2 identifies which port to read (0=COM1, and 1=COM2). The byte
read is stored in variable1 (which may be an integer or string type
variable). Before executing this statement you should first check to
see if there is data waiting to be read. Executing this statement when
data is not waiting can cause your PC to "hang" until data is received
at the hardware serial port. The example below illustrates how to
determine if data is waiting to be received.
Example:
OPENCOM(2,0,0,3,0)
PORTSTAT = COMSTAT(0)
DATAREADY = ZBIT(8,PORTSTAT)
IF DATAREADY = 0 THEN NODATAWAITING:
A$=RECEIVE(0)
These statements do the following. The first retrieves the status of
COM1 to the variable PORTSTAT. The second checks to see if bit 8 is on,
DATAREADY will contain 1 if so, otherwise it will contain 0. Since Bit
8 is used to determine if data is waiting to be received from the port,
if DATAREADY NOT = 0 then the program will RECEIVE data from the port to
variable "A$".
Comments:
Variable1 can be either a string or integer type variable.
However, if variable1 is a string, bear in mind that you cannot directly
receive a NULL (ASCII Code 0), since NULL is used to delimit the end of
a string in ASIC. However, if in the above example data was waiting at
the port but A$ contained "" after the receive, you would know that the
character received was a NULL. This is not a problem if variable1 is an
integer variable.
See also:
OPENCOM,SEND,COMSTAT
Page - 86
REM
Format: REM free form comments
Description:
This statement is used to insert comments into your program.
Everything following REM is treated by ASIC as a comment.
Example:
REM The compiler will ignore this line
RESTORE
Format: RESTORE
Description:
This statement allows you to READ data from DATA statements after
you have already READ it once.
Example:
DATA 0
READ A
RESTORE
READ B
In this example, "READ A" causes variable "A" to be set to 0. Now, the
DATA statement is "used up". There is no more data left on it to be
read. The RESTORE resets the DATA so that the next statement "READ B"
will result in "B" being set to 0. If the RESTORE was not done, the
contents of B would be undefined.
See also:
READ, DATA
Page - 87
RETURN
Format: RETURN
Description:
Used to return from a GOSUB call.
Example:
GOSUB PRINTIT:
END
PRINTIT: PRINT "IT"
RETURN
In the above example, the word "IT" will be printed on the screen. The
RETURN statement causes program execution to resume on the statement
following the corresponding GOSUB statement. In this example, control
will be returned to the END statement.
Comments:
Executing a RETURN statement without having first executed a GOSUB
statement could cause unpredictable results.
See also:
GOSUB
RIGHT$
Format: string1 = RIGHT$(string2,integer1)
Description:
This statement will copy the rightmost integer1 characters from
string2 to string1.
Example:
A$=RIGHT$("RED RIDING HOOD",4)
After the execution of the above statement, the variable A$ will contain
the string "HOOD".
See also:
MID$, LEFT$
Page - 88
RMDIR
Format: RMDIR string1
Description:
This statement will delete an empty directory from disk. String1
should contain the name of the directory to delete. If ASIC is unable
to delete the directory, it will set the System ERROR variable. A list
of ERROR codes is listed in the Error Messages Chapter of the ASIC
Manual.
Example:
RMDIR "C:\WORK\TEST"
IF ERROR = 0 THEN SUCCESS:
After execution of this code, the directory TEST under directory WORK
will be deleted (if it had no files or subdirectories in it, and if it
is not the current directory for drive "C").
See also:
MKDIR,CHDIR
Page - 89
RND
Format: integer1 = RND (integer2)
Description:
This statement will return an integer number in the range of 0
through 32767 for normal integers, and in the range of 0 to
2,147,483,647 for long integers. This random number will be stored in
integer1. Integer2 is a dummy argument and can be any valid integer
value.
Example 1:
A& = RND(0)
After execution of this statement "A" will contain a number between 0
and 2,147,483,647 inclusive.
Example 2:
RANDOMIZE
DIEROLL=RND(0)
DIEROLL=DIEROLL MOD 6
DIEROLL=DIEROLL+1
PRINT "YOU ROLLED A";DIEROLL
The above example demonstrates how to generate a number in a given
range. In this case, the range will be 1-6, which would be suitable for
simulating the roll of a die. The above example will generate the
simulated die roll, and print the result.
Comments:
In BASICA/GWBASIC, RND always returns a value between 1 and 0.
Page - 90
RTRIM$
Format: string1=RTRIM$(string2)
Description:
This statement will remove all trailing spaces from string2 and
store the resulting string in string1.
Example:
A$=RTRIM$("XYZ ")
After the execution of this statement, the variable "A$" will contain
"XYZ".
See also:
LTRIM$
Page - 91
RUN
Format: RUN string1
Description:
This function can be used to load and execute other programs
compiled with ASIC or another compiler. String1 represents the name of
the program to execute. If an error occurs when ASIC attempts to RUN
the program, it will set the system ERROR variable to 255. Otherwise,
the ERROR variable will be set to the value of the return code of the
called program (which is 0 unless the called program specifies
otherwise).
Example:
RUN "OTHER.COM"
Comments:
String1 must contain the FULL pathname of the program
(ie,"\directory\progname.COM") only if the program is NOT in the current
directory. You must include the file extension on the file name (for
example, use "MYPROG.COM" instead of just "MYPROG", or use "MYPROG.EXE"
instead of "MYPROG").
At this time, RUN and CALL are functionally equivalent, with one
exception. RUN does not accept program arguments, but CALL does.
CAUTION:
You may use the debugger with programs which contain "CALL" or
"RUN" statements. However, the programs you call should not themselves
contain debugging code. For example, if A.ASI calls B.ASI, then make
sure you compile B.ASI with the "Debugging Code" option OFF before you
try to debug program A.ASI. Failure to do so will cause the debugger to
behave erratically. This also applies to programs you write using other
compilers, since they also use the same interrupt that ASIC uses (INT 3)
for debugging purposes.
See also:
CALL
Page - 92
SCREEN
Format: SCREEN integer1
Description:
This statement will transfer the computer between text mode and
graphics modes. Integer1 must be an integer constant with a value of 0,
1, 2, 7, 9, or 13. These modes are described in the table below. The
"Mode" column identifies the value of integer1 to specify on the SCREEN
command to select that graphics mode. The "Graphics Resolution" column
has three numbers. The first identifies the number of rows of pixels
supported in this mode. The second number identifies the number of
columns. The third number identifies the number of colors which may
displayed on screen at one time. The numbers in the "Text Resolution"
column tell you how many rows, columns and colors you may display on the
screen when displaying text. The adapters column identifies the type of
graphics adapter required to use this mode.
Mode Graphics Resolution Text Resolution Adapters
----- ------------------- --------------- -------
0 None 25 x 80 x 16 Any Adapter
1 200 x 320 x 4 25 x 40 x 4 CGA/EGA/VGA
2 200 x 640 x 2 25 x 80 x 2 CGA/EGA/VGA
7 200 x 320 x 16 25 x 40 x 16 EGA/VGA
9 350 x 640 x 16 25 x 80 x 16 EGA/VGA
13 200 x 320 x 256 25 x 40 x 16 VGA
Example:
SCREEN 13
After execution of this statement, the PC will be in Graphics Mode 13
which will allow you to display 200 rows by 320 columns of pixels in 256
different colors. Up to 25 rows and 80 columns of text can be displayed
in up to 256 colors. And finally, mode 13 requires a VGA Graphics Card.
Comments:
Any program which uses the SCREEN command should issue a "SCREEN 0"
command before terminating. Otherwise, the screen will not be reset
properly when you return to DOS.
See also:
PSET, PRESET, POINT, ZMODE
Page - 93
SEND
Format: SEND (data1,integer2)
Description:
This statement is used to send one character to a serial port. The
port should initialized with OPENCOM prior to using this statement.
Data1 may be any valid data type (integer or string, variable or
constant) and it should contain the character to be sent to the port.
Integer2 identifies which COM port to send to (0=COM1, 1=COM2).
Example:
OPENCOM(2,0,0,3,0)
SEND ("X",0)
The above code will open COM1 at 300baud, 1 stop bit, 8bit character
size, with no parity. It will then send the character "X" to COM1.
See also:
RECEIVE,COMSTAT,OPENCOM
SOUND
Format: SOUND integer1,integer2
Description:
This statement will generate a sound on your computer speaker with
a frequency of integer1, and a duration of integer2. Frequency should
be in the range of 0 to 32767. ASIC, however, only checks to see that
it is non-negative.
Example:
SOUND 400,20
Execution of the above statement will produce a short beep.
Comments:
ASIC "frequencies" values go from high to low. That is, a
frequency of 0 is the highest, and 32767 is the lowest.
Page - 94
SPACE$
Format: string1=SPACE$(integer1)
Description:
This statement will return a string containing integer1 ASCII space
characters.
Example:
A$=SPACE$(10)
B$="<"+A$
B$=B$+">"
After execution of these statements, variable "B$" will contain the
string "< >".
See also:
STRING$
STR$
Format: string1 = STR$ (integer1)
Description:
This statement will convert integer1 to a string format and store
the string format in string1.
Example:
A=1234
A$ = STR$(A)
After execution of these statements, A$ would contain the string "1234".
See also:
VAL
Page - 95
STRING$
Format: string1=STRING$(integer1,integer2) <--Format 1
string1=STRING$(integer1,string2) <--Format 2
Description:
This statement will return a string containing integer1 characters
of ASCII value integer2 (Format1). If format 2 is used, this statement
will create a string containing integer1 characters. Each of these
characters will be the same as the first character of string2.
Example 1:
A$=STRING$(8,111)
After execution of these statements, variable "A$" will contain the
string "oooooooo".
Example 2:
A$=STRING$(5,"xyz")
After execution of these statements, variable "A$" will contain the
string "xxxxx".
See also:
SPACE$
Page - 96
TIME$
Format: string1 = TIME$
Description:
This statement will retrieve the current time from the PC's system
clock. The time will be retrieved and stored in String1, in the format:
"HH.MM.SS".
Example:
CURTIME$=TIME$
PRINT CURTIME$
After execution of the above statements the current time (as per the
PC's internal clock) will be displayed on the screen.
Comments:
Note: if the time printed is wrong, you have probably not set the
system clock. Most older XTs and PCs do not have a battery to preserve
the DATE and TIME in the system clock, so you have to set them each time
you power up the PC. Most ATs and newer PCs have a battery backup, so
that the date is preserved for you.
Unlike GWBASIC/BASICA, you cannot set the system time with TIME$,
however, you can set the system time from DOS by typing TIME.
See also:
DATE$, TIMER
Page - 97
TIMER
Format: integer1 = TIMER
Description:
This statement will retrieve a timer count from the PCs hardware
circuitry. The timer count will be placed in integer1. The timer count
is in "clock ticks". A "clock tick" occurs in the PC approximately 18.2
times per second. The PC is continually incrementing this clock
counter. This statement can be used to time the duration of events.
Example:
CLS
PRINT "PRESS A KEY"
STARTCNT&=TIMER
LOOP:X$=INKEY$
IF X$="" THEN LOOP:
ENDCNT&=TIMER
ELAPSED&=ENDCNT&-STARTCNT&
ELAPSED&=ABS(ELAPSED&)
ELAPSED&=ELAPSED&/18
PRINT "IT TOOK YOU APPROXIMATELY";
PRINT ELAPSED&
PRINT " SECONDS TO PRESS A KEY"
The above code fragment will time how long you wait to press a key in
seconds. You could modify it easily to display in clock ticks, which
would provide much more accuracy, if you deleted the statement which
divides the ELAPSED count by 18.
Comments:
Note that it is necessary to use the absolute value of ELAPSED&
since the clock counts is stored as unsigned integers. ASIC integers,
on the other hand, are signed. If integer1 is a long integer variable,
then TIMER retrieves the full PC timer value. However, if a normal
integer variable is specified as integer1, then ASIC retrieves the least
16 significant bits from the PC timer.
See also:
DATE$,TIME$
Page - 98
UCASE$
Format: string1=UCASE$(string2)
Description:
This statement will convert all lowercase letters in string2 to
uppercase, and store the resulting string in string1.
Example:
A$=UCASE$("123 Main St, USA")
After execution of this statement, the variable "A$" will contain the
string "123 MAIN ST, USA".
See also:
LCASE$
VAL
Format: integer1 = VAL (string1)
Description:
This statement will attempt to convert string1 into an integer
value, and it will store the result in integer1.
Example:
A$ = "12345"
A = VAL (A$)
After execution of these statements, variable "A" would contain the
value 12345.
See also:
STR$
Page - 99
VARPTR
Format: integer1 = VARPTR (variable1)
Description:
This statement will return the address of a variable variable1 and
store it in integer1. This may be used to peek and poke values directly
into a variable.
Example:
A$ = "XYZ"
B = VARPTR(A$)
C = PEEK (B)
PRINT C
After execution of these statements the screen would display the number
88 which is the number for the ASCII character "X".
See also:
PEEK, POKE
WHILE/WEND
Format: WHILE condition
WEND
Description:
This statement will execute those statements which are between the
WHILE and the WEND statements as long as the "condition" is true. The
operand "condition" is one of the following:
integer1 > integer2
string1 > string2
integer1 = integer2
string1 = string2
integer1 < integer2
string1 < string2
Example:
PRINT "PRESS A KEY TO CONTINUE"
A$=""
WHILE A$=""
A$=INKEY$
WEND
In this example, the program will pause until the user presses a key.
WHILE statements may be nested 25 levels deep.
Page - 100
WIDTH
Format: WIDTH integer1
Description:
This statement will set the screen to 40 column text or 80 column
text mode only. The only two valid values for integer1 are thus 40 and
80. In ASIC, WIDTH 80 is equivalent to executing SCREEN 0. Also, WIDTH
40 is equivalent to executing SCREEN 1. If you use WIDTH 40, you should
always reset the screen back to WIDTH 80 before terminating your program
with END. Otherwise, your PC will be left in 40 column mode.
Example:
WIDTH 40
The above statement would put the PC in 40 column mode.
ZBIT
Format: integer1 = ZBIT(integer2,integer3)
Description:
This statement is used to determine if a single "bit" in an integer
variable is set to "1". Integer2 represents the bit to be tested. It
should be in the range 0 to 15. Integer3 represents the integer
variable or constant to be tested. The result of the test is returned
to integer1. If the bit was set, integer1 will be set to "1",
otherwise, integer1 will be set to "0".
Example:
GAMEPORT = INP(513)
TRIGGER = ZBIT(4,GAMEPORT)
IF TRIGGER = 1 THEN TRIGGERPRESSED:
In this example, the joystick port is read, and its status is placed in
the variable "GAMEPORT". The bit which represents the trigger for
joystick 1 is then tested using ZBIT. If the trigger bit is set, then
the program would transfer to the label "TRIGGERPRESSED:". Note that
the above code assumes that a game card is present in the computer.
Comments:
This statement is an extension over GWBASIC/BASICA, although it is
possible to perform similar tests in GWBASIC/BASICA with the boolean AND
statement.
Page - 101
ZMODE
Format: integer = ZMODE
Description:
This command returns a code which indicates whether a color or
monochrome card is active in the system. ZMODE returns a value of 1
when a color card is detected, and a value of 0 for monochrome.
Example:
A = ZMODE
IF A = 1 THEN CONTINUE:
PRINT "This program requires a Color Card to Run"
END
CONTINUE: REM rest of code follows here
The above code fragment will check for a color card, if not found the
program will terminate with an appropriate message. Otherwise the
program will continue.
Comments:
This statement is an extension over BASICA/GWBASIC.
Page - 102
A S I C
Chapter 8
Compatibility with GWBASIC/BASICA
In general, although ASIC does not support all options on every BASIC
statement, those it does support work like they do in BASICA/GWBASIC.
The known exceptions are listed in this chapter.
INKEY$
This statement is compatible, however ASIC does provide an
extension over GWBASIC/BASICA. If an extended key is pressed (e.g. F1-
F10), ASIC returns the scan code for the extended key, and sets a
special system variable "EXTENDED" to a value of 1. For non-extended
keys, the "EXTENDED" variable will contain 0.
FILE HANDLING
ASIC provides no EOF statement or ON ERROR statements. Instead,
ASIC sets a special system variable when an error occurs during file
I/O. This special variable is called "ERROR" and it is set after every
file I/O statement (OPEN/INPUT#/PRINT#/CLOSE, etc) to either 0 to
indicate no errors, or a non-zero value. If a non-zero value is
present, an error has occurred. The specific errors are identified in
chapter 10.
FILE FORMAT
ASIC Files are written with 2/4 bytes per normal/long integer in
binary format, instead of string format as in BASICA/GWBASIC. Strings
are written as a sequence of ASCII characters terminated by an ASCII
null, or optionally with no NULL terminator.
PUNCTUATION
ASIC permits use of punctuation that it does not require to allow
you to enter statements in their familiar GWBASIC/BASICA Formats. For
example:
A = ABS (B(1))
This statement is valid in both ASIC and in GWBASIC/BASICA.
However, ASIC ignores the parenthesis and comma. Thus ASIC will
actually accept the following formats as alternatives to the above:
A = ABS B 1
A = ABS B 1,,,,,,)))))
Page - 103
FOR/NEXT
FOR/NEXT loops always fall through the body of the FOR at least one
time in ASIC. This does not happen in BASICA/GWBASIC. For more
information on this, refer to Chapter 7.
RND
RND (N) returns a value from 0-32767 for normal integers and 0-
2,147,483,647 for long integers instead of 0 to 1 as in BASICA/GWBASIC.
LOCATE/CSRLIN/POS
Coordinates are specified in range 0-24 and 0-79 instead of 1-25
and 1-80.
PSET/PRESET/POINT
Coordinates are specified in row/column order instead of column/row
order.
BLOAD/BSAVE
File formats are not compatible with GWBASIC/BASICA. BLOAD
requires offset and the number of bytes to read.
OPENCOM/COMSTAT/SEND/RECEIVE
These statements provide serial port support in ASIC. In
GWBASIC/BASICA this is provided by OPEN/INPUT#/PRINT#.
DATE$/TIME$
ASIC allows you to retrieve the system date and time, but will not
allow you to set new system date/time values.
CALL/RUN
These statements perform functions similar to their GWBASIC/BASICA
counterparts, but function differently. Refer to the keyword reference
for the appropriate keyword for details on their operation.
Page - 104
EXTENSIONS OVER BASICA/GWBASIC
CODE COMMAND$
INT86 FILEPOS
FIND LCASE$
LTRIM$ MOD
RTRIM UCASE$
ZBIT ZMODE
The statements above are extensions over BASICA/GWBASIC.
Page - 105
A S I C
Chapter 9
Technical Details/Tips
This chapter contains technical information and tips regarding ASIC.
COMPILER LIMITS
Maximum Source Program Size: Unlimited - Command Line
809 Lines - Integrated Environment
Maximum Object Program Size: 64k bytes (.COM Format restriction)
Maximum Source Line Length 128 bytes - Command Line
80 bytes - Integrated Environment
Compiler Symbol Table Size: 750+ Symbols
Maximum Number of Arrays: 25
FOR/NEXT Nesting Depth 25
IF/THEN/ELSE Nesting Depth 25
WHILE/WEND Nesting Depth 25
Compiler Memory Requirements 305k - Command Line
405k - Integrated Environment
COMPILER OPERATION
ASIC is a single pass compiler written entirely in C (Borland Turbo
C Version 2.0). Each source statement is translated directly into
machine code. ASIC compiles 100% in memory for maximum speed. The
compiler does not require any disk work space. ASIC generates a minimum
of error checking code. This is because the ASIC philosophy stresses
execution speed. This does place greater responsibility on the
programmer to check for out of bounds conditions, etc..
Page - 106
MEMORY OPTIMIZATION
ASIC 3.0 provides 32 bit long integers in addition to 16 bit normal
integers. This allows you to store much larger numbers, however,
nothing in life is free. Long integers will increase the size of the
resulting ".COM" file by approximately 475 bytes. If you are not using
long integers, be sure to compile with the "Extended Math" Option turned
OFF so that ASIC does not include these unneeded bytes in your ".COM"
file. Otherwise, ASIC will include the long integer support code in your
".COM" file, even if you never create a single long integer! Note: by
default, this option is turned off in both the command line and
integrated version of the compiler.
Also remember that ASIC's debugging option increases your ".COM"
file size. So don't forget to recompile your program with the
"Debugging" Option turned off (after you have finished debugging it, of
course).
Page - 107
DEBUGGER LIMITS
Maximum Concurrent Breakpoints 20
Maximum Concurrent Watches 10
Maximum Symbol Length 30 Characters
Maximum Symbols Same as Compiler
Maximum Source Statements 809 Lines
DEBUGGER OPERATION
When you select the "Debugging code" compiler option, the ASIC
compiler inserts additional machine language instructions into your
program. It inserts a single statement at the beginning of your program
(specifically, INT 3) which allows it to gain control. When the ASIC
editor is loaded, it saves the existing INT 3 vector, and installs the
ASIC Debugger as INT 3. In this way, when your program begins
executing, the INT 3 statement that ASIC inserted in your program causes
a transfer of control to the debugger. Once the debugger gains control,
it can set or remove additional breakpoints as needed in your program,
plus provide access to the video memory and variable memory locations
with the Swap, Watch, Unwatch, and Modify Commands. When you exit the
ASIC editor, ASIC deinstalls the debugger from INT 3, and restores the
original interrupt 3 vector.
The compiler also creates a file with a ".DBG" extension which
contains the symbolic information needed by the debugger (ie, variable
names and offsets, and source statement offsets).
DEBUGGER OVERHEAD
Running a program in debugging mode adds a small amount of overhead
to your program (both compiled code size, and execution speed).
Specifically, the size of the debugging code will be (approximately):
CodeSizeIncrease = 1 + LinesOfSourceCode
Note that the actual increase will usually be less than the above, since
DIM, DATA, REM, and blank source lines do not require debugging code.
The reduction in execution speed is very slight in most cases (for you
assembly language programmers out there, a single NOP instruction is
executed for each source line).
Page - 108
STORAGE FORMATS
Normal integers are stored in ASIC as two bytes, with the low order byte
appearing first (as per Intel conventions). Long integers are stored in
ASIC as four bytes, with the least significant word first, followed by
the most significant word. Within these two words, the least
significant byte appears first followed by the most significant byte.
String variables are stored as FIXED 80 character strings terminated by
an ASCII null character for a total length of 81 characters. String
constants are stored with 1 byte per character in the string followed by
a terminating ASCII null character. Each element in an array requires
two bytes. (Don't forget arrays have an element zero (ie DIM A(2) is
comprised of A(0), A(1), and A(2)).
Examples:
Item Data Type Storage Requirements
A Integer Variable 2 bytes
17 Integer Constant 2 bytes
A& Long Integer Variable 4 bytes
55555& Long Integer Constant 4 bytes
A$ String Variable 81 bytes
"ABC" String Constant 4 bytes
"A" String Constant 2 bytes
DIM A(10) Integer Array 22 bytes
DIM A(1) Integer Array 4 bytes
DIM A&(10) Long Integer Array 44 bytes
As you can see, string variables are expensive in terms of storage
space. Since string constants are stored at actual length +1, It is
MUCH more efficient to store short strings as constants in ASIC in terms
of storage space. There is no performance advantage to constants over
variables, however.
In disk files, strings and integers are written out in the above
formats. Note that unlike GWBASIC/BASICA, integers are NOT expanded
into strings when written, and conversely, not converted from strings to
integers when read. String variables and constants are written out as
ASCII strings terminated by a null character (however, the null can be
suppressed). Thus, string variables when written to disk, take the same
space byte for byte as string constants.
The reason behind fixed length string variables was avoidance of string
"garbage collection". In addition to slight performance advantages,
there is the added benefit of providing a string memory address which
never changes. Thus once VARPTR retrieves the address of a variable,
you never have to worry about it changing.
Page - 109
MEMORY MAP
The following describes the structure of the ".COM" file created by
ASIC. All addresses are in Hexadecimal.
Description Address Range
------------------------------ -------------
Program Segment Prefix (PSP) 0000 - 00FF
(Created/Required by DOS)
Transfer to Program Code 0100 - 0102
String Conversion Buffer 0103 - 0109
Input Buffer 010A - 015B
Screen Width 015C
Color/Attribute Byte 015D
Screen Graphics Mode 015E
Cursor Position 015F - 0160
File Control Table 0161 - 0169
ERROR System Variable 016A - 016B
System Subroutine Vectors 016C - 017F
EXTENDED System Variable 0180 - 0181
RND Seed 0182 - 0185
Math Work Area 0186 - 018D
DEFSEG System Variable 018E - 018F
Start DATA Block Pointer 0190 - 0191
Current DATA Block Pointer 0192 - 0193
Reserved for future use 0194 - 0195
System Subroutines 0196+
|
|
v
Data Segment Address Varies
|
|
|
v
Code Segment Address Varies
|
|
|
v
^
|
|
Program Stack (builds downward) FFFF
Page - 110
A S I C
Chapter 10
Error Messages
This chapter contains compiler messages, run-time error messages, and
File I/O Error Codes.
COMPILER ERRORS
These messages indicate errors in your source program. Those which
begin with "** E" indicate "fatal" errors, which prevent ASIC from
successfully compiling your program. Warnings begin with "* W" and
indicate possible errors and informative messages which will not prevent
ASIC from generating an executable ".COM" file.
FATAL ERRORS
** E001 ** File Extensions must be either ".ASI" or omitted
ASIC requires source programs to have the extension ".ASI". Rename
your source file with the DOS "RENAME" command to the name "file.ASI",
where "file" is your source program name. Then resubmit the compile.
** E002 ** File Name specified is too long
The source file may be identified by a file name up to 124
characters long including disk drive specifiers and sub directory names.
Move the source program to a directory which may be specified within
this length.
** E003 ** Error Opening File: xxxxxxxx.xxx
The file indicated by "xxxxxxxx.xxx" could not be opened by ASIC.
This error can be issued when ASIC attempts to read your source file, or
when it writes any one of the possible output files (".COM", ".LST", or
".SYM"). If indicated file is your source program name, verify the
spelling, and either make sure it is in the same directory as ASIC, or
specify the full path name for the file. If the indicated file is an
output file, the error is usually a result of a write protect tab on the
diskette or insufficient disk space.
Page - 111
** E004 ** DIM Statements must precede all others except REMs
In ASIC, DIM statements must appear before all other statement
types, except REM statements (or blank lines).
** E005 ** Too many characters in source line
Source program lines in ASIC are limited to 120 characters. Change
the indicated source line, so that it fits within this limit.
** E006 ** Unmatched Quote ('"') in source line
A string constant was found with either no opening or closing quote
mark. Quotation marks must be matched in pairs within source lines.
** E007 ** Token in source line > 82 characters long
Individual tokens in ASIC are limited to 82 characters in length,
regardless of type. A token is a group of letters and/or numbers
delimited on either side by a space or math symbol. Example, even
though string constants are limited to 80 characters, ASIC considers the
"token" to include the quotation marks. In this case, however, ASIC
detected a token longer than the longest possible token, the string
constant. Check for "tokens" or "words" more than 82 characters long in
the indicated source line.
** E008 ** More than 30 tokens in source line
Since all ASIC statements require less than 30 tokens, ASIC will
flag any statement which contains more than this number. A token is a
group of letters and/or numbers delimited on either side by a space or
math symbol.
** E009 ** Keyword Unknown: xxxxxxxxx
ASIC detected the symbol indicated by "xxxxxxxx" in your source
line, but it was not a valid variable name, constant, label, or ASIC
Function Name.
** E010 ** Symbol Table Space Exhausted
The symbol table is used by ASIC to keep track of your variables,
constants and labels. It is also used to hold information used in
FOR/NEXT processing, and internal system subroutine generation. Reduce
the number of LABELS, VARIABLE NAMES, or CONSTANTS in your program, and
recompile.
Page - 112
** E011 ** Symbol Incomplete Reference Space Exhausted
This table is a sister table to the Symbol Table, it contains
references to LABEL type symbols which have been defined in the symbol
table. Try to reduce the number of references made to LABEL symbols
within the program and recompile.
** E012 ** No keywords in source line
Every ASIC source program line must contain an ASIC keyword (eg.
"PRINT", "=", "GOSUB", etc).
** E013 ** Syntax Error
The "catch-all" error for ASIC. This error is usually issued when
ASIC has identified an error in the parameters for an ASIC keyword. The
best way to find this error is to refer to the entry in the Keyword
Reference (chapter 7) for that particular keyword.
** E014 ** Undefined Symbol: xxxxxx
ASIC detected a LABEL "xxxxxx" which was referenced, but never
defined in the program. A label is considered to be defined when it is
the first token on the source line. A reference to a label occurs when
a label name appears elsewhere in the source statement
Example: PRINTIT: PRINT "hello" <---Defined
GOTO PRINTIT: <--Referenced
** E015 ** Compiled Code Exceeds 64k-Can't fit in .COM file
Your source program is too large to fit in the .COM file format.
Eliminate extraneous variables and program statements. Note: REM
statements do NOT generate any output code, so elimination of REM
statements will not alleviate this problem.
** E016 ** Integer Constant Not in range +32767 to -32767
The above range of numbers is the maximum which can be contained in
integer format in ASIC. Reduce the constant so that it falls within the
specified range.
** E017 ** Duplicate Label: xxxxxx
The indicated label "xxxxxx" was defined more than once in the
program. Reduce the multiple definitions to a single definition and
then recompile.
Page - 113
** E018 ** Second FOR defined for variable with no intervening NEXT
FOR/NEXT Statements cannot be nested with the same variable name.
VALID INVALID
FOR I=1 TO 10 FOR I=1 TO 10
FOR J=1 TO 20 FOR I=1 TO 20
NEXT J NEXT I
NEXT I NEXT I
** E019 ** For/Next Table Space Exhausted
An unlimited of FOR/NEXT statements can exist, however, they can be
"nested" to a maximum depth of 25.
** E020 ** NEXT without FOR
A NEXT statement was found, however it was not preceded in the
source program with a matching FOR statement.
** E021 ** FOR without NEXT at Source Line NNNNN
The indicated source line NNNNN contains a FOR statement, for which
no NEXT statement was ever found.
** E022 ** Invalid Option: x
An invalid compile option was specified. Review Chapter 5 for a
list of valid compile options.
** E023 ** More than 63000 bytes in Data Segment
An ASIC program can be up to 64k bytes in size. Of this total,
63000 bytes can contain program variables and constants, leaving at
least 1k for program code. Reduce the number of variables and constants
in your program.
** E024 ** Too many arrays defined
A single ASIC source program can contain up to 25 arrays.
** E025 ** Re-DIMension of previously DIMensioned variable
Only one DIM statement can be specified per array name.
Page - 114
** E026 ** Invalid subscript on Array
A subscript was found which is not valid. Either ASIC expected
more or less subscripts than were present, or ASIC detected a subscript
which was itself an array. Subscripts on arrays may only be non-array
variables and/or integer constants.
** E027 ** String Arrays Are Not Supported
A DIM statement specified a string variable type. Only integer
arrays are supported.
** E028 ** Comfile Buffer - Memory Allocation Failed
ASIC attempted to allocate memory for an internal buffer . This
memory allocation failed. More memory is required. If you have any
TSRs loaded in memory, remove them and try again.
** E029 ** Codeseg Buffer - Memory Allocation Failed.
ASIC attempted to allocate memory for an internal buffer. This
memory allocation failed. More memory is required. If you have any
TSRs are loaded in memory, remove them and try again.
** E030 ** Code Segment Memory Exhausted
ASIC will attempt to allocate 64k of memory to use a work space to
hold the code generated by your program statements. This message
indicates that the amount of memory it was able to allocate was not
sufficient to hold the code generated by the program you are trying to
compile.
** E031 ** Data Segment Memory Exhausted
ASIC will attempt to allocate 64k of memory to use a work space to
hold the data segment for your program. This message indicates that the
amount of memory it was able to allocate was not sufficient to hold the
data generated by the program you are trying to compile.
** E032 ** Insufficient Memory to Run ASIC
You don't have enough memory to run ASIC. If you have any TSRs
loaded, try removing them and re-compiling.
** E033 ** Edit Buffer Memory Allocation Failed
ASIC attempted to allocate memory for the edit buffer in the
integrated environment, but was unable to. If you have any TSRs loaded,
remove them from memory, and try again.
Page - 115
** E034 ** DATA Statements Must Precede All Except DIMs or REMs
If you wish to use the DATA statement in ASIC, you must place them
all at the beginning of your program following any DIM and/or REM
statements (or blank lines).
** E035 ** Requires 32 Bit Math--Recompile W/Math Option
The compiler found a statement containing long (32bit) integer
variables or constants. You must compile with the Extended Math Option
turned on to be able to use long integer math. Turn on the "Extended
Math" Option from the Compile Menu in the ASIC Integrated Environment,
and recompile the program. If you are compiling from the MS DOS command
line, recompile using switch "E".
** E036 ** Error Allocating Debugger Screen Memory
ASIC was unable to allocate memory to save the screen output from
your programs when you run your program in debugging mode in the ASIC
integrated environment. You could try removing some TSRs from your
AUTOEXEC.BAT file. Then try running ASIC again.
** E037 ** IF Statements Nested Deeper Than 25 Levels
An unlimited number of block IF statements may be used in your
program, however, they may be nested to a maximum depth of 25 levels.
See the IF statement documentation in Chapter 7 for more information.
** E038 ** ELSE Statement Without Preceding IF Statement.
ASIC found an ELSE statement but did not find a preceding block IF
statement. See the IF Statement documentation in Chapter 7 for more
information.
** E039 ** ENDIF Statement Without Preceding IF Statement.
ASIC found an ENDIF statement with no preceding matching IF
statement. See the IF statement documentation in Chapter 7 for more
information.
** E040 ** Block IF Statement Without Matching ENDIF Statement.
When using the block IF format of the IF statement, you must always
specify a matching ENDIF statement. See the IF Statement documentation
in Chapter 7 for more information.
Page - 116
** E041 ** WHILE Statements Nested Deeper Than 25 Levels
An unlimited number of WHILE statements may be used in your
program, however, they may be nested to a maximum depth of 25 levels.
See the WHILE statement in Chapter 7 for more information.
** E042 ** WEND Statement Without Preceding WHILE Statement
ASIC found a WEND statement with no preceding matching WHILE
statement. See the WHILE statement documentation in Chapter 7 for more
information.
** E043 ** WHILE Statement Without Matching WEND Statement
Each WHILE statement must be followed by a matching WEND statement.
See the WHILE statement documentation in Chapter 7 for more information.
Page - 117
NON-FATAL WARNINGS
* W001 * Last Statement Not END -- END supplied
Warning only. ASIC expects the last statement of a program to be
an END statement. If it does not find one, it generates one for you.
* W002 * Printer Not Ready - 'P' Option Ignored
You selected the "Printer" option, but ASIC was not able to access
the printer. Make sure the printer is online before compiling with the
'P' option.
* W004 * Edit Buffer Full--File Truncated
While loading a file, the edit buffer filled before ASIC reached
end-of-file. The file is truncated in memory. IF YOU SAVE THE FILE
AFTER RECEIVING THIS MESSAGE, PART OF THE FILE WILL BE LOST ON DISK. IT
IS RECOMMENDED THAT YOU EITHER EXIT ASIC IMMEDIATELY, OR THAT YOU SAVE
THE TRUNCATED FILE UNDER A NEW NAME SO THAT THE ORIGINAL FILE IS NOT
DAMAGED.
* W005 * Edit Buffer Full
ASIC issues this message when the edit buffer is full and you
attempt to insert a line. Delete some unnecessary source lines to
create space in the edit buffer.
* W006 * Source/Dest of Block Copy/Move May Not Overlap
You attempted to move or copy a block of lines to a destination
line which was within the source block of lines. Execution of this
block move/copy would result in an endless series of copies or moves.
Move the cursor outside of the highlighted block of lines, and try
again.
* W007 * Source Program Modified. Recompile? (Y/N)
You selected the RUN or TRACE option of ASIC. ASIC has noticed
that you have modified the source. You should answer "Y" here to cause
ASIC to recompile your program before running it. If you instead answer
"N", ASIC will execute the existing copy of the compiled program, which
will not contain your latest changes.
* W009 * File has been modified. Save File Now? (Y/N)
You have told ASIC to exit back to DOS, but the edit buffer has
been modified. You should answer "Y" so that ASIC will save your
changes back to disk. If you answer "N" here, any changes you have made
to your program since the last SAVE command will be lost.
Page - 118
* W010 * Too Much Debugging Info-Truncating
ASIC could not handle all of the debugging information it found.
This error should not occur.
* W011 * Variable Not Found
During the processing of a Watch, Unwatch, or Modify Command, you
specified a variable name which ASIC could not find in the debugging
information. Checking your spelling for possible errors. Also, verify
that you have compiled your program with the Debugging compiler option
turned ON.
* W012 * Maximum Number of Variables Are Being Watched
You are already "watching" the maximum number of variables that
this version of ASIC supports. "Unwatch" one of the variables in the
watch window. This will allow you to "Watch" a new one.
* W013 * There Are No Variables Being Watched
You selected the "Unwatch" command. However, there are no
variables in the watch window to "Unwatch". Before this command may be
used, you must first have added a variable to the Watch window using the
"Watch variable" command.
* W014 * Unable to Load/Run Program
When ASIC attempted to load and run either the compiler or your
program it detected an error. This is due to one of two reasons.
First, ASIC could not find the program on disk. If compiling, make sure
that the ASICC.EXE file is in the same directory as the ASIC.EXE file,
and make that directory current. The second reason that you might get
this error is that there may be insufficient memory available on your
PC. In this case, you either need to free up more memory (by removing
TSRs etc), or you could execute your program or the compiler from the
DOS command line. For more information on compiling from the command
line, see Chapter 5--Stand-alone Compiler Options.
* W015 * Can't Set Breakpoint There--No Code Generated For That Source
Line
You attempted to set a breakpoint and either 1) You haven't
compiled with the Debugging Compiler Option turned on, or 2) You have
tried to set a breakpoint on a line which did not generate any object
code. Thus, breakpoints cannot be set on REM or DATA statements, for
example. If you are sure that you have compiled with the above option
turned on, then try setting the breakpoint on another nearby statement.
Page - 119
* W018 * Your Program Must Be Running To Use This Function
You selected a function which is only operable when you are running
a program (which was compiled with the debugging compiler option turned
on). After your program terminates, this function is not available.
* W019 * Function Unavailable Until You Terminate Your Program
You selected a function while your program was running in debugging
mode. Before you can execute this function you must either Abort your
program, or allow it to Run until normal termination. Both the Run and
the Abort Options are available on the "Run" Menu.
* W020 * Invalid Debug (.DBG) File Format
ASIC attempted to access the symbolic debugging information file
created by the compiler for your program. It was able to locate the
file, but detected an error in the format while reading it. Make sure
that the version number of both the ASIC Integrated Editor and the ASIC
Compiler are the same. The version number is displayed on the top line
of the editor screen, following the word "ASIC". It is also displayed
on the compiler status screen while a compile is executing.
* W021 * Maximum Number of Breakpoints Already Set
You have attempted to set another breakpoint, but the maximum
number that this version of ASIC can support are already in use. Remove
one of the existing breakpoints you have set. This will free one up for
your use elsewhere.
* W022 * Can't Open ASIC.IDX File
You requested online help for an ASIC keyword. This function
requires a file called "ASIC.IDX" provided with your ASIC package, and
ASIC could not find this file in the current disk directory. Copy this
file from your ASIC package to the directory in which you are running
ASIC and try again.
* W023 * Can't Open ASIC.DOC File
You requested online help for an ASIC keyword or menu option. This
function requires a file called "ASIC.DOC" provided with your ASIC
package, and ASIC could not find this file in the current disk
directory. Copy this file from your ASIC package to the directory in
which you are running ASIC and try again.
Page - 120
* W024 * Can't Open ASICM.IDX File
You requested online help for an ASIC menu option. This function
requires a file called "ASICM.IDX" which was provided with your ASIC
package, and ASIC could not find this file in the current disk
directory. Copy this file from your ASIC package to the directory in
which you are running ASIC and try again.
* W025 * No Help Available For Selected Item
There is no online help available for the item you selected. The
information should be available in the ASIC Manual.
* W026 * Unable To Write ASIC.CFG File
You told ASIC to save your current Integrated Environment Options.
ASIC attempted to do so, but was not able to. Your options were not
saved to disk. This is usually caused by one of two things: 1) The
disk is full, or 2) The disk is write-protected. If the disk is full,
delete some unneeded files and try again. If the disk is write-
protected, remove the write-protect tab from the disk and try again.
* W027 * Debugger Can't Fully Save User Screen--Insufficient Memory
ASIC was not able to allocate enough memory to save the screen
output from your program while it was running in debugging mode in the
integrated environment. As a result, the screen displays may become
garbled. You should normally only see this message when your program is
using a high resolution EGA/VGA graphic mode on machines with very low
memory, or you have many TSRs installed. Either purchase more memory,
go to a lesser graphics mode, remove some TSRs from the AUTOEXEC.BAT
file, or run your program outside of the integrated environment.
Page - 121
RUN TIME ERRORS
Divide Overflow
This message indicates that your program attempted to divide by
zero.
Page - 122
SYSTEM ERROR CODE VALUES
After most commands which access the disk, ASIC sets a special "ERROR"
variable to indicate success or failure of that command. After you
execute one of these commands, you can reference this variable as a
regular variable in your program, to determine the outcome of the
command(eg. "IF ERROR = 000 THEN OKAY:").
ERROR Codes Set by BLOAD
000 No Error
002 File Not Found
003 Path Not Found or File Doesn't Exist
004 File Not Found
005 File Access Denied
006-255 Read Past End of File
ERROR Codes Set by BSAVE
000 No Error
002 File Not Found
004 File Not Found
005 File Access Denied
006-255 Disk Full
ERROR Codes Set by CALL
000-254 Return Code from Program (Zero If Not Set by User Program)
255 Error Loading/Running Program
ERROR Codes Set by CHDIR
000 No Error
003 Path Not Found
ERROR Codes Set by CLOSE
000 No Error
006 Invalid Handle
095 Cannot Close File -- File is not Open
ERROR Codes Set by FILEPOS
000 No Error
001 Invalid Function Number
006 Invalid Handle
098 File mode not Random or Append
Page - 123
SYSTEM ERROR CODE VALUES (Continued)
ERROR Codes Set by FIND
000 No Error
002 File Not Found
018 No More Files Match Search Criteria
ERROR Codes Set by GETDIR
000 No Error
015 Invalid Disk Drive Specification
ERROR Codes Set by INPUT#
000 No Error
005 Read Access Denied
006 Invalid File Handle
096 Input String Truncated at 80 characters
(this error code is not set when you specify NONULL)
098 File Not Open for Input or Random Modes
099 End of File
ERROR Codes Set by KILL
000 No Error
002 File Not Found
005 Access Denied
ERROR Codes Set by MKDIR
000 No Error
003 Path Not Found
005 Access Denied
ERROR Codes Set by NAME
000 No Error
002 File Not Found
003 Path Not Found or File Doesn't Exist
005 Access Denied
017 Not Same Disk Drive
ERROR Codes Set by OPEN --- Mode Input
000 No Error
002 File Not Found
004 File Not Found
005 File Access Denied
254 File Number Already in Use
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SYSTEM ERROR CODE VALUES (Continued)
ERROR Codes Set by OPEN --- Mode Output, Append, or Random
000 No Error
001 Invalid Append Function
003 Path Not Found
004 No File Handle Available
005 File Access Denied
006 Invalid Append Handle
254 File Number Already in Use
ERROR Codes Set by PRINT#
000 No Error
005 File Access Denied
006 Invalid File Handle
097 File Not Open for Output, Append, or Random Modes
255 Disk Full
ERROR Codes Set by RMDIR
000 No Error
003 Path Not Found
005 Access Denied
006 Can't Delete Current Directory
016 Can't Delete Current Directory
ERROR Codes Set by RUN
000-254 Return Code from Program (Zero If Not Set by User Program)
255 Error Loading/Running Program
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