Advanced Programming - AMSTRAD cpc 6128 User Instruction

Advanced programming
Side 2 of your system discs package contains a number of programs intended for use
by advanced and system programmers. It is recommended that the user consult
SOFT 971- A Guide to
CP/M
Plus, or other reference works.
Working with CP/M 2.2
This section is intended to highlight the differences when operating using
CP/M 2.2.
CP/M
2.2 is loaded from the first two tracks of a System disc. The bootstrap sector is
different from that used to load
CP/M
Plus and care should be taken not to confuse
them. Although it is possible to use Vendor, IBM, and Data format discs in either disc
drive, operational considerations usually restrict their use to the second disc drive.
Unless special action is taken by the
CPIM
program (as F I LEe 0 PY does for
example) then
CPIM
2.2 will not allow you to write to a disc unless it has been 'logged
in'. Furthermore, the type of disc format (System, Data, or IBM) is only
re-determined when a disc is logged in. For the main disc drive within the computer
(Drive A) this takes place whenever
CP/M
2.2 returns to the Direct Console Mode, or
when [CONTROl]C is typed at the A> or B> prompt. For an additional drive (Drive
B) this takes place the first time that the disc in Drive B is accessed, after Drive A has
been logged in.
Should you try writing to a disc that has not been logged in, the infamous error
message:
Bdos Err on
,drive>: RIO
.... will be displayed. Press any key to continue. If the changed disc was also of a
different format then a read or write error will occur. Type C to continue.
If you receive software on a disc in Vendor format, then in order to use it
conveniently, you may either copy it to a
CPIM
2.2 system disc by using F I LEe 0 P Y
or PIP, or alternatively convert the disc to a system disc by adding your
CP/M
to it.
This is achei ved with the BOO T G E Nand S Y S G E N commands. Carefully read the
End User Licence Agreement in this manual (Appendix 1).
S Y S G E N (with no parameters) is a specialised copier program which prompts for a
source and destination disc, and copies the
CP/M
2.2 system tracks from one disc to
another. BOO T G E N similarly copies Sector 1, track 0 (the loader) and the
configuration sector from one disc onto another.
The D I R command does not accept parameters (other than a file specifier). The
filenames are not sorted into any particular order, but the po si tion of the filename in
the D I R display indicates the position of that file's entry in the disc directory.
AMSDOS and CPIM Chapter 5 Page 33