Date : Fri, 15 Jan 1993 12:47:08 -0500
From : Jay Sage <sage@ll.mit.edu>
Subject: Re: ZCPR3 on California Computer Systems Machine
A manual installation of ZCPR3 requires some modest changes to the system
BIOS. First, the BIOS must be moved down in memory to open up space for the
ZCPR3 buffers (multiple command line buffer, environment buffer, path
buffer, named directory register, shell stack, etc.). If MOVCPM is
available, it should be able to handle that job. In addition, the buffers
must be initialized. If you have the CBIOS source code, this poses no
problems in principle. If you don't have source, then you have to patch
into the cold boot code (before it merges, as it sometimes does, with the
warm boot code). Writing this code is not difficult in principle, but
putting all the pieces together -- the parts you write and the existing BIOS
object code -- can be a little tricky.
Fortunately, none of this is necessary any more in the overwhelming
majority of cases. NZCOM takes care of everything automatically. A menu-
based utility allows you to design your system configuration or
configurations. If you have more than one, you can change among them
without rebooting. In fact, you can change operating systems right in the
middle of a multiple command sequence, which means that alias scripts can
potentially do it automatically. System modules are provided in a run-time
relocatable format so that nothing has to be assembled or reassembled for
use at a new address. Even the command processor, BDOS, and BIOS interface
modules can be reloaded while the system is running! In short, an NZCOM-
created Z-System is superior to a manually installed system. There are only
two drawbacks: a memory penalty of 256 bytes and a financial cost of $49.
The manual that comes with NZCOM provides a minimal introduction to Z-
System. The most valuable source of information is The Computer Journal
magazine, where I have been writing a regular column for about six years and
where several other Z-System developers and users have also published
frequently.
End of INFO-CPM Digest V93 Issue #11
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