EXORcisor was: Re: fpo9 wasRe: [Coco] NitrOS-9 Team:

[Joel Ewy]

Willard Goosey wrote:
> ...
>> The Exorcisor is an old system that Motorola developed in the
>> 70's. 
>>     
>
> I've heard of it, and knew it could have a 6809.  Operating systems
> that ran on it include: MDOS, OS9, SDOS, and SDOS/MT.  The 68K version
> was apparently called the EXORmacs.  I also know that people wired
> both 8" and 5.25" floppy drives up to it.  And that's all I know
> about it.  I would love to know more.
> ...
I have two of the 6809 EXORcisor MicroModule 17 boards, complete with
original boxes, manuals (including complete schematics), and
un-filled-out warranty cards.  They are meant to be used in an EXORbus,
which I (of course) don't have.  The bus uses the same big 100-pin
connector as an S-100 bus though, and the CPU modules can really be used
as stand-alone SBCs if you provide them some power.  This is what I
intend to do with at least one of them. 

The boards are approximately 6x10".  They have a 6809 (note, not the 'E'
model that's in the CoCo), a 6821, a 6840 (programmable timer) and 2
6850 ACIAs.  Most of these I/O signals are brought out to .1 spaced card
edge connectors on the opposite edge of the board from the bus.  These
also have solder pads nearby that dual-row headers could be soldered
into.  There are 5 28-pin sockets that can be used for (E)(P)ROMs or
SRAMs, ranging in size from something like 2Kx8 to 8Kx8.  You can change
the way these sockets are addressed using a combination of jumper blocks
and configuration Bipolar PROMs.  They came from the factory with
programmed configuration PROMs, and if you have appropriate memories and
like Motorola's memory map, you can just use those.  I have a programmer
I can use to burn new PROMs, and I got a couple blank ones a few years
back so I can reconfigure these things.  But mine came with no firmware,
like a monitor or bootloader.  They are clocked at 1MHz with a
(socketed!) 4MHz crystal.

I'd eventually like to make (Nitr)OS-9 run on them.  It would need to be
LI, 6809.  I would need to build a new Clock module that would work with
the 6840, come up with drivers for the 6850s, and probably some kind of
generic driver for the 6821, plus a new Init module.  I had originally
planned to hook a CoCo FDC up to the EXORbus, but that was when I had a
different idea of what I wanted to use them for.  Now I'd rather hack
that FDC for High-Density and use it on a CoCo, and leave the EXORmodule
diskless.  I might cook something up with a SitePlayer Telnet or some
such.  Maybe I could rig up a dongle with a serial EEPROM if it needs a
little non-volatile local storage.  It would be fun to use it for home
automation and temperature monitoring.

But before I try to port OS-9, I have some source for a 6809 TinyBASIC
that I can try, which should be a simpler job.  It uses the 6850 and
needs very little modification to run on the MicroModule 17.  And I
think I can get it to run from a 2K EPROM, which means I won't have to
burn one of my precious few Bi-PROMs to test it out.

If you want more info about them, email me privately.

JCE