Date   : Wed, 24 Oct 1990 07:41:48 GMT
From   : zephyr.ens.tek.com!tektronix!nosun!techbook!fzsitvay@beaver.cs.washington.edu (Frank Zsitvay)
Subject: Need info for an S-100 bus system

In article <PLTFR2w163w@ijpc.UUCP> ianj@ijpc.UUCP (Ian Justman) writes:
>fzsitvay@techbook.com (Frank Zsitvay) writes:
>
>> Not exactly.  I tried using z80mu to write a zmd overlay.  I could
>> assemble it but the loader barfed under the emulator.
>
>What loader were you using?  And does it say what calls it puked
>on?
>
   i was using cp/m load.com.  and the function was number 26, set DMA
address.

>> Z80MU does
>> not support such things as setting the DMA address for cp/m, among
>> other things.
>
>What do you expect for an emulator?  It probably could be done
>but I dunno...
>
   what do i expect from an emulator??   an emulation that works.  granted
it is free software (virtually) so i can't beef much, but all the DMA
address in cp/m does is tell the operating system where the next disk
operating is supposed to read/load the data from/to.

   this is used quite a bit in some utilities.  when loading a file 
for processing, the application reads in a disk block, increments
the DMA address by 128, and reads the next one, and so on.  it's a 
bit faster than doing a read/block move approach.
 
   as far as emulating a z80, it does a good job.  emulating cp/m is
another story.
 


  And now for something completely different...
 
  I have a california computer systems s100 machine that i am trying
to get back into working order.  it has three boards, a model 2810 Z80
cpu, a model 2065 64k RAM board, and a model 2422 Disk controller board.

  My problem is:
 
      What is the power-on jump address supposed to be set at so the
coldstart rom will be executed??  when i got the board it was set at
0000H, which didn't work.  I have no documentation with this machine,
so i don't want to resort to the trial and error method, checking all
65536 addresses, although by educated guesses it could be narrowed down 
to 512 or so.
 
      Also, if anyone else out there has a machine like this one,
would i be able to get a copy of the boot disk??  i have a bios
listing for this system, but don't want to go through the hassle of
building cp/m onto a floppy, and also the only machine i have here
(with 8 inch drives) is a tandy model 12, which has an ersatz cp/m
implementation.   (doesn't support movcpm and sysgen, which are a 
necessity for this type of port.)
 
   and another request...  i also have a kaypro 2 (1983), and i need
a boot disk for it.  

-- 
fzsitvay@techbook.COM - but don't quote me on that....

American Oil Company motto - Bend over, We'll pump!!!