Dave Lowe: Assempro 1987.07.12/Lowe_Assempro_1987_07_12.img/READ_ME

Text File | 1985-11-20 | 7.7 KB | 223 lines

IMPORTANT NOTICE:

Since AssemPro has been updated, we have to make a few
additions on this diskette file.

1)  Since the program turned out to be longer than anticipated, and
a number of programs were added, the diskette is pretty full of data.
Before you start working with AssemPro, you should format a data diskette,
and copy the TOS and DEMO folders to it. Then you'll have enough room to
save programs to be assembled. Remember to have the AssemPro original
diskette in drive A.

2)  For reasons of versatility, and because of memory needs, AssemPro
requires one of the following hardware configurations:

-  Atari 260 ST with TOS in ROM
-  Atari 520 ST with TOS in ROM
-  Atari 260 ST expanded to 1Meg with TOS in ROM or on disk
-  Atari 520 ST expanded to 1Meg with TOS in ROM or on disk
-  Atari 520 ST+ with TOS in ROM or on disk
-  Atari 520 ST/M with TOS in ROM or on disk
-  Atari 1040 ST with TOS in ROM or on disk

3) When you want to delete a file, choose and delete your file from the
file selector box; you can continue deleting files from that box, until
you click CANCEL.

4) The following operations have been added to AssemPro:

a<<b :  Shift a (binary) b bits to the left. This is the equivalent of
        a*2^b.
a>>b :  Shift a (binary) b bits to the right. This is the equivalent of
        ABS(a/2^b)
?a   :  Determine the number of most significnt bits from a. This cor-
        responds to the logarithm of base 2 from a.

These three new operations work with integers (no leading characters).
Examples:

1<<3       = 8
1024>>5    = 32
?8         = 3
?1024      = 10
?32        = 5
%1011<<3   = %1011000
%1010>>3   = %1
?%1010     = 3
?(1<<a)    = a

5) Changes to the assembler:

Local variables are valid only when between two global variables, as
already described in the manual. These are undefined above and below.

Redefinable global variables do not influence the valid range of local
variables, however, when you've already defined them!

So, the following program is correct:

REDEFINABLE@ = 0

GLOBAL_1:
\LOCAL_1 = 27
REDEFINABLE@ = \LOCAL_1
\LOCAL_2 = 1 << \LOCAL_1
GLOBAL_2:

Symbols will be replaced by the assembler as strings, e.g.:

SYMBOL EQU BlahBlahBlah

From the line SYMBOL, the assembler creates BlahBlahBlah.

However, this does not apply to the symbol definition, which
can't make much sense of this. So, the assembler replaces the line

SYMBOL EQU BlahBlahBlah

with the variable SYMBOL, but it doesn't read BlahBlahBlah, and signals
an error.

When the occasion arises that a symbol which stands in the first column
of a line needs replacement, then you can write a $ character in front
of the symbol. For example:

DEFINE:MACRO $\1,$\2 ;<= These $'s signal the system to handle the
                     ; \1 and \2 as symbols.
$\1=\2               ;<= \1 should be replaced
ENDM

DEFINE CONSTANT,7

Will put CONSTANT=7 in from the assembler.

These special examples don't make much sense as they stand.
There are, however, a number of complex applications where you can
use this, such as in converting C structures to assembler format.

6) Additional assembler commands:

IFD variable

Tests for whether a variable has been defined, and operates like a
normal IF command. Variables should not be handled as symbols, that is,
when they've been defined, and replaced as the respective character strings,
and the assembler eventually goes to error checking.

IFND variable

This is the opposite of IFD. This variable test for whether the variable
has NOT been defined. Here the same restrictions apply as for IFD. Both
commands can be given as an arithmetic expression. It can then test
whether all variables are defined or not.

It is difficult when the variable is only undefined during pass 1. It will
then only assemble program sections bracketed by IFND-ELSE or ELSE-ENDIF on
pass 1. This is only allowed when this program section only contains
variable definitions and no 68000 commands. So, variable definitions
should give no forward references:

 IFND FLAG

FLAG=1
M:MACRO
 ;
 ENDM
K1=15
K2=LABEL  ;<<<<<<<<< K2 contains the value 0, since the label has not
          ;yet been defined during pass 1.
 ENDIF

\1=0      ;Here we have a problem....

LABEL:

You must define them with local variables directly following the ENDIF.
These belong namely to the last global variables defined. During pass 1
it is the constant K2, but on pass 2 it is the last global variable.
The result: The assembler doesn't find \1 during pass 2.

8) When in the editor, the cursor moves the next tab to the left (!) when
you press <Shift> and <Tab>.

9) Additions to the debugger:

When you click "Execute program" in the debugger, you can state an option
of whether the program just loads, just starts, or loads AND starts. When
you want to debug a program, do the following:

-  Load the program with load only.
-  Insert breakpoints, or whatever you prefer to do, to get the program
   back to the debugger
-  Now call the "Execute program" call, and start the program. This is
   necessary for initialization, without crashing the loaded program.
   Always start from the beginning of the program.   Now you don't need to
   select the filename anymore.

When you want to get the program running again after returning to the
debugger, either click the "Program start" field, or press <Control><S>.

10)  Here is some advice for all of you who want to single-step through
     the operating system:

When you use the mouse and not the keyboard to control the debugger, the
problems described in the manual do not occur. These parameters aren't
spot-checked by GEMDOS, XBIOS or BIOS routines. Examine the KBSHIFT
function for a demonstration.

11)  Some other improvements worth mentioning:

When you execute a double-click on the debugger field "From address",
you get the beginning of the program found in memory, and the
starting address given in the Info line.

Besides that, when you single-click "From address", the following appears:

*=$__________

12)  Furthermore, we should mention some other items not made clear
in the manual.

When you wish to assemble programs from magazines or books, you must have
the relocatable option on, otherwise the assembler will signal errors
where none exist.

This is allowable only with relocatable programs when a label is given as
the destination of the command, e.g.,

MOVE D0,PICT_HIGH

This applies to the Hardcopy program!!

PS:  You can no longer have Relocatable and PC-relative code active
simultaneously. This is merely a cosmetic correction, not a functional one.

When defining constants you absolutely should use the equal sign, not
the EQU command, which is used in other assemblers. The program's func-
tion will be unimpaired, but the assembler speed will be affected,
and so will your aggravation.

Finally, some tips about the debugger:

When you want to debug a program which you have assembled first, or which
you have loaded from the File menu selection "Load", you should remember to
use no BSS segments.

When you start it, though, your program drops into an empty area of memory.

Besides that, you must put such a program into unnecessary memory, by
beginning any program with executing SETBLOCK.

The same applies to the program end. This should not be ended with
TERM (GEMDOS 0), since there is no basepage there.

When you have tested the incorrect areas of your program, removed the
breakpoints and left the debugger, then load and start the program
(see point 9).

We wish you much enjoyment with your AssemPro ST.

DATA BECKER Duesseldorf W. Germany
ABACUS SOFTWARE Grand Rapids MI USA