OT-ish: Build-it stuff

Chuck Guzis cclist at sydex.com
Wed Jun 14 13:29:41 CDT 2006


On 6/14/2006 at 11:08 AM Don Y wrote:

>Not sure I understand what *you* are being asked to do...

Develop an emulator for the box itself.

>Do you know what format the disk image is in?  I.e. is it recognizeable
>as a DOS FAT-12, etc.  (gives you some clues)

Oh, I've already identified the OS--it's MTOS-86--but that doesn't mean
it's known to me.  The filesystem is CP/M-ish.  But the app itself is tied
into the OS in a single unified whole--there is only one file holding
everything.

>Can you share those strings?  Or, are you bound by NDA?
>They might be recognizeable messages to identify the OS
>(QNX, VRTX, etc.)

No NDA here--messages are of the nature "Unexpected Interrupt"--about a
half-dozen such things, all of them, your basic debug message-and one
reference to an "integrated debugger"--and no application-specific
identifiable ASCII in the remainder of the code.  My suspicion is that the
ASCII is sent to some diagnostic port and not to the main display.  But the
code referencing the debugger messages might be a place to start.

>Given the timeframe -- and your description of the peripherals -- it
>could likely be an 80186 design.  (IIRC, that was available around
>'81/82).  

Almost certainly not--figure 18 months average lead time from design to
production.  I worked with early steppings of the 80186 back then and they
weren't ready for prime time yet.  Besides, I don't see any references to
setting up the relocation block, which ought to be about the first thing to
occur.   I'm very sure that this is a garden-variety 8086/8088--no
80186-specific instructions to be seen anywhere (e.g. PUSHA).

I'd look for I/O devices if I was certain of what they were.  No keyboard,
just a numeric-type keypad, some kind of one-line display, RS-232 and some
sort of interval timer and a floppy drive.  The RS-232 was used as a data
link, not to drive a terminal.

Like I said, if this were a hobby thing, I'm sure I could suss it out given
as much time as I needed.  But I'm on the clock on this one.

Cheers,
Chuck





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