FORMAT.COM | A program used to make new discs ready for
use. |
LOAD.COM | A program used to convert the output of the
assembler from an ASCII listing of hex into a
.COM file, ready to run. |
MOVCPM.COM | A program used to tailor CP/M to systems with
differing amounts of memory. |
PIP.COM | Used to transfer files from one device to
another and to join files together. Can do an
awful lot and is very useful. |
STAT.COM | Not 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.COM | A program to allow you submit a file filled
with commands, which CP/M will carry out in
sequence, usually described as batch mode. |
SYSGEN.COM | A 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.