Volume 2 · Number 3 · July 1982

Page 16 of 37
FORMAT.COMA program used to make new discs ready for use.
LOAD.COMA program used to convert the output of the assembler from an ASCII listing of hex into a .COM file, ready to run.
MOVCPM.COMA program used to tailor CP/M to systems with differing amounts of memory.
PIP.COMUsed to transfer files from one device to another and to join files together. Can do an awful lot and is very useful.
STAT.COMNot only does this one give you statistics about the size of files, it is also used to tell CP/M which devices are available for it to use.
SUBMIT.COMA program to allow you submit a file filled with commands, which CP/M will carry out in sequence, usually described as batch mode.
SYSGEN.COMA program used to copy CP/M itself onto a new disc.

Both Zaks and Fernandez and Ashley give good descriptions of how to use these programs and there would be little point in going over the same ground again. There are a few things the dedicated machine code “freak” like myself needs to know about some of them, however. To start with, the text editor was designed (it seems) ta be used with a teletype rather than a VDU. It is a very powerful editor, but not at all easy to use and the only valid reason for continuing to use it would be poverty. Even masochists draw the line somewhere before ED.COM! The assembler also displays its historical origins clearly, as it uses the hideous Intel mnemonics that were developed from the 8080 mnemonics when the Z80 first appeared. If you don’t recognise SHLD and STA as being Z80 mnemonics, you will not find this assembler at all easy to get on with. I have no idea why it can’t put its output on the disc without the help of LOAD.COM.

This information came as quite a shock to me when I started to use CP/M, as I had not seen any such critisms in the press before I bought the system. At first sight, there would appear to be considerable difficulty in store far the user who hopes to do more than just run other peoples’ programs. The advantages of CP/M are such that these problems should not be considered overwhelming. The cure is a simple one, provided you can afford a little more software, after the already considerable cost of the disc system itself. Several software packages consisting of an editor, assembler and debugging aids are available – the one I use is sold by Hisoft. Their editor gives back the ability to move the cursor all over the screen, at the expense of not running on other CP/M systems, which is no problem, and the assembler recognises sensible mnemonics. The debugger has several excellent facilities absent from the standard DDT.COM , and has a better display than Nas-Sys when single stepping. It also includes a disassembler which is very useful.

In my next article I will describe how ta use the CP/M input and output routines in your programs, with some examples.

Page 16 of 37