Date   : Fri, 13 Jul 1990 14:47:13 EST
From   : SAGE@LL.LL.MIT.EDU
Subject: QX-10 and Z-system

   This is in response to Will Rose's recent message.

>> I decided the best way to play it was to move the BDOS down, and put the
>> ZCPR buffers between the BDOS and BIOS.

   Even if you could figure out how to do this, it does not result in the
best solution.  There are quite a few CP/M programs that calculate addresses
on the assumption that the BDOS is 0E00H below the BIOS entry point.  They
will fail after you have made your modification.  You would also have to
perform a code relocation on the BDOS, since it would now be running at a
different address, and you would have to change the BIOS warmboot so that it
would load the BDOS and CCP to the new addresses.

>> However, I couldn't find out how (where) the QX10 kept the location of
>> the BDOS for use in eg. the  warm-boot code;

   Is it not kept on the system tracks of the diskette the way it is on
other CP/M computers?

>> Jay Sage came across one of my pleas for help on a BBS, and wrote me a
>> note to say that a lot of people in his area were running the Z-system on
>> QX-10s with no real problems.  I don't know which version they were
>> running; it may be later than 3.3.

   The ones I know about most recently are using NZCOM.  It is not a
question, in any case, of the ZCPR version.  They all run more or less the
same way.  Later versions just have improved features.  ZCPR33 is a MAJOR
improvement over ZCPR3; ZCPR34, the latest version, has some nice additional
features but nothing anyone really has to have.

>> I recently got a price for the current ZCPR/ZRDOS to run on a QX-10 from
>> Jay Sage's company (~$140 total) and decided it just wasn't cost
>> effective.  If you ran the new ZCPR with NOVADOS (is that possible?) it
>> would only cost you ~$75; pricey, but might be worth it.

   There was apparently a major misunderstanding here.  The cost of NZCOM is
$70, and that provides a COMPLETE, automatically installing, and fully
reconfigurable (statically and dynamically) Z-System, INCLUDING the ZRDOS
disk operating system replacement code.  It is very easy, if not trivial, to
substitute NOVADOS or Z80DOS.  In fact, you can change DOSs at will, even in
the middle of a command line!  You can then experiment easily with different
versions of the DOS without having even to reboot the computer.

   The finest replacement DOS, in my opinion, is ZDOS (the ZSDOS/ZDDOS pair
of datestamping DOSs).  The full price of that package is $75; it is reduced
to $60 for owners of NZCOM (or ZRDOS in any form obtained legitimately).
There is no need to purchase ZDOS with NZCOM.

   If $70 stretches the budget too much and/or one would rather invest
significant amounts of time, then a manual installation of ZCPR33 makes
sense.  This is not easy if you do not have source code for the BIOS or a
version of MOVCPM that will move the whole system down in memory.

   Otherwise, there are many reasons, as I set forth in one of my TCJ
columns, to prefer NZCOM -- for technical and performance reasons, not just
for the ease of installation.  The Ampro on which my Z-Node BBS is running
still has a manually installed Z-System, but that is only because I don't
have time to fix things that are not broken.  If I were doing it over, I
would certainly use NZCOM instead, as I do on my Televideo 803H and Amstrad
PCW8512 (actually, Z3PLUS on the Amstrad).