Re: [N8VEM-S100:708] Getting CPM 2.2 running on a set of N8VEM S-100 cards

[Don Caprio <cap...@uxpro.com>]

Andrew, are there any S-100 Z80 boards available?

Sent from my iPhone

On Feb 19, 2012, at 10:27 AM, "Andrew Lynch" <LYN...@YAHOO.COM> wrote:

> 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
>> 
> 
>