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-
-
- CHAP01.TXT
- Version 1.01 01/29/85
- Leonard Gilberg 74126,2044
- Robert Flagg 72466,2332
-
- THE JOYS OF ASSEMBLY
-
- This "Cookbook" is the brainchild of Robert Flagg
- [72466,2332], Leonard Gilberg [74126,2044], Bonnell Frost
- [74076,223] and others, who, with the blessing of Frank
- Fallon (SYSOP), felt it would be helpful if some members of
- the Sig, new and otherwise, had an oppor tunity to see the
- struggles of members new to CP/M learning the ins and outs of
- using ASM, LASM3 and/or ZASM. Some of the "Recipes" here are
- the contribution of several members of the Sig who are grateful
- to have the opportunity to pass along information given to them
- by more ex perienced members when they were struggling too.
-
- Too often, members are afraid to ask for help,
- thinking that the question is too basic or that they will appear
- "dumb". The only dumb question is the unasked one because
- there are always others eager to pass along advice and excited
- about the opportunity to repay the favors given them in the
- beginning, by helping someone else along.
-
- Should this Cookbook be approved and placed in "use", we
- will all be happy to have been a part of it, especially, if it is
- of help to any one.
-
- Normally, files with the extension .ASM, when down-
- loaded, are transformed into files with the extension .COM after
- the application of some version of ASM.COM and LOAD.COM. At that
- time, they are ready to run as in the case of any other .COM
- file you have by simply typing the filename without the .COM
- extension.
-
- In some cases, for example where the program is
- installed as a patch, in WordStar for instance, you will stop
- after the use of ASM so that the file will have a .HEX extension.
- You will not, in such cases, use the LOAD.COM procedure. There
- are some rarer variations of this, but they are beyond the scope
- of this discussion.
-
- For the sake of terminology, the .ASM is referred to
- as the "Source Code" file and the .COM file as the "Object Code"
- file.
-
- You may one of those who "almost" understand what is
- being said about a particular program or action, but really are
- not sure because some of the words are strange. You may be
- afraid that if you ask what the word or words mean, everyone
- will think you're so dumb they won't want to talk to you anymore.
- Perish the thought! For those of you who feel you need it, here
- is our attempt at some sort of table of definitions.
-
- DEFINITIONS
-
- ALGORITHM - Generally, a special method of solving a
- certain kind of problem.
-
- ASSEMBLERS - Those programs, such as ASM.COM, LASM.COM &
- ZASM.COM, which take an Assembly Language Source File and create
- two other files--the object code .HEX file and the diagnostic
- .PRN file.
-
- COMPILER - A language translator which takes as input source code
- in a high-level language such as Fortran, C, Pascal, or Cobol and
- generates as output either assembler-input code or object code
- directly.
-
- DDT - An utility program, by Digital Research Institute (DRI),
- supplied with CP/M and used to "debug" programs. Hence the
- name DDT (cute, huh?). Used to break a program down into its
- 8080 mnemonics so that those who know what they are can make the
- changes desired. DDT is RAM-memory oriented.
-
- DU - Another utility program, designed by Ward Christensen
- which works, essentially, the same as DDT, with a little
- different configuration, and now followed by DUU.COM. DU is
- oriented to work on disk memory.
-
- ENTRY POINTS - The specific location in a program where an
- Overlay or other modification to the program begins.
-
- GENERIC - A non-specific class, general in nature.
-
- HEX - A "shorthand" reference to Hexidecimal values, usually
- known as Intel format, and created by the ASM program. Also
- used as a file extension, i.e., Filename.HEX. Also, a situation
- which exists when Mother Nature discovers that you forgot to put
- surge protectors on your equipment and calls down the elements
- to teach you better.
-
- INITIALIZATION - A command or sequence of commands which readies
- equipment or a program for execution as desired. Normally used
- in connection with setting equipment, such as printers, to their
- default values.
-
- INTERACTIVE - In the computereze climate, this is usually a point
- in a program where you input information from the keyboard
- or "interact" with the program.
-
- LANGUAGE - A word which describes the particular type of instruc
- tion to a computer. The "language" must be structured in such
- a way that the computer "understands" and is able to convert
- the instructions contained in the "language" into object code.
- Examples could be Assembly, Cobol, Fortran, C, Pascal, Forth,
- etc.
-
-
- LOAD - The program, usually supplied with CP/M, which takes the
- .HEX file generated by the ASM program and converts it into a
- .COM program ready to run. LOAD.COM and MLOAD.COM are examples.
-
- MACHINE LANGUAGE - Binary code, a series of 1's and 0's, which is
- the only instruction that a computer understands. Every other
- language is either translated, interpreted, compiled, assembled
- or loaded so as to, ultimately, reach machine language.
-
- MICROPROCESSOR - Usually, a silicon chip (such as Intel's 8080 or
- Zilog Z-80, such as is used in the Kaypro).
-
- MNEMONICS - "Short-hand" or abbreviated instructions required by
- a particular language processor in order for the compiler or
- assembler to generate object code.
-
- OBJECT FILE - The file which contains the binary code which you
- always wanted when you started with the "Source File." Usually
- this is a .HEX or a .COM file.
-
- OFFSET - Has more than one meaning. In 8 bit operation, such as
- CP/M, usually means a hexidecimal position or address other than
- the "usual" or "expected" location or address. Normally given as
- an auxilliary address in the command where it is used.
-
- OVERLAY - A method allowing a group of changes to be made in an
- existing program. The "overlay" program is typically a smaller
- program which, when "overlaid" on an existing program, changes
- part of the instructions in the existing program. Overlays are
- commonly used to configure "generic" software to enable it to run
- on specific hardware setups.
-
- PATCH, PATCHING - The process of changing a program byte-by-byte.
- Often used when smaller changes are required to customize a
- program.
-
- SCREEN CLEARING - The act of giving or causing to be given a
- command or series of commands which cause the CRT to clear or
- become blank.
-
- SEQUENCE - A series of commands, structured to give a computer
- specific instructions to accomplish. Usually, must be given in a
- pre-set or predetermined order.
-
- SOURCE FILE - The program written in a human-understandable
- language which assemblers or compilers will convert to machine-
- understandable object code.
-
- SPECS - Short for specifications.
-
- SUB - An extension (.SUB) for a source file of commands for the
- SUBMIT or EX program.
-
- ZCPR - A Z80 Command Processor replacement for the CP/M Console
- Command Processor (CCP) which performs a new and different set of
- commands as well as the familiar CP/M commands. Author is Rick
- Conn.
- e to enable it to