RE: [N8VEM-S100:704] Getting CPM 2.2 running on a set of N8VEM S-100 cards

["Andrew Lynch" <LYN...@YAHOO.COM>]

Hi Neil!  Thanks!  Leon posted a set of CP/M 3.0 disk images for the S-100
Z80 CPU board

http://n8vem-sbc.pbworks.com/w/browse/#view=ViewFolder&param=Disk%20Images

John has instructions on the S-100 Z80 CPU board here

http://s100computers.com/My%20System%20Pages/Z80%20Board/Z80%20CPU%20Board.h
tm

and more instructions on bringing up CP/M 3.0 from scratch here

http://s100computers.com/Software%20Folder/CPM3%20BIOS%20Installation/CPM3%2
0FLOPPY%20BIOS%20Software.htm

If you start with Leon's example you'll need to adjust it for the S-100
Serial IO board for CONIN, CONOUT, etc.

There are probably useful things in the N8 directories but there are
significant differences in the memory mapping and other things so there will
be limited applicability of the N8 CBIOS.

I hope this helps!  Thanks and have a nice day!

Andrew Lynch


> -----Original Message-----
> From: n8vem...@googlegroups.com [mailto:n8vem-
> s1...@googlegroups.com] On Behalf Of nbreeden
> Sent: Friday, February 17, 2012 12:32 PM
> To: N8VEM-S100
> Subject: [N8VEM-S100:704] Getting CPM 2.2 running on a set of N8VEM S-
> 100 cards
> 
> Having assembled my alpha S-100 VDU I sat down to start testing it and
> realized I was missing a critical part; the ability to boot CPM on my
system
> based on N8 S-100 cards.
> 
> My system Config:
>   Z-80 Master CPU - tested and known good
>   4 megabyte Static RAM card - 1MB installed - tested and known good
>   ZFDC - tested and known good
>   Serial I/O - tested and known good
>   EPROM - not tested
> 
> You may ask how I tested these without being able to boot the system, this
is
> what I have done:
> 
> To test the SERIAL I/O card I wrote code that I burned into EPROM for the
> CPU card; this card tested the Serial I/O card.
> 
> I've taken the ZAPPLE monitor along with code from a Z-80 monitor John
> wrote (www.s100Computers.com) and created my own version of it. One of
> the functions it has is the ability load HEX files produced by TASM. I
ported
> John's code for the ZFDC from CPM programs to standalone programs under
> TASM. I then assemble them and via the text file send function in Teraterm
I
> loaded these into RAM for execution. I have been able to adjust the ZFDC
> and have been able to format 3.5"
> floppies.
> 
> Next using the monitor I wrote a set of playback files (again for
> TeraTerm) that using the PORT I/O function of my monitor along with the
> LOAD/DUMP memory functions was able to test all 16K blocks of the 1MB
> memory space to verify the basic functionality (I know the block selects
> work, I know the RAM can be written and read back).
> 
> The Monitor has John's code to read the boot sector from a floppy and
start
> it to bring up CPM.
> 
> So, now I need a floppy with CPM to boot.
> 
> Having completed a ZETA and having it running well with 2 3.5"
> floppies this seems like a good platform to write the system to floppy; it
> already has the tools to get the image to the RAM Disk (XM) and the
program
> to write the system to floppy (WRITESYS.COM).
> 
> Next I checked out the BUILD directories from Doug's SVN site and began
> digging through them to understand how it works; this is what I have
> concluded in looking at it:
> 
> Porting the CBIOS for the S-100 config listed above should be straight
> forward, John already provided the code to get the basics working.
> 
> Building a CPM image (the SYS file) and the standalone file (the COM
> file) using looks pretty straight forward.
> 
> Questions:
> 
> 1) It's unclear to me if the ROM image can be used; the N8 does some
tricks
> to map SRAM or EPROM into the Z80 address space; using the extended
> address space of the Z80 CPU card this would be possible however only the
2
> lower 16K blocks can be swapped. Can this be done?
> Should it be done?
> 
> 2) Should I add the functionality to build a CPM image for the S-100
system to
> the current build tree or do we want to start a new tree?
> 
> 3) Ultimately I hope to have a CPM floppy image downloadable so someone
> can build the basic board set; image a floppy and boot the system using
the
> default jumper settings. Is there value in doing this?
> 
> -Neil
>