Multibus-I Users ?? - test-drb@ccmp.vtda.org

28 May 1999

This board is definitely dedicated for disk I/O.  It supports 8" and 5.25"
floppy drives with a connector for each, and apparently two 5.25" hard disks
as well.  It uses a WD 1010 chip as did most of the early PC HDC's.  The
floppies are run with a WD 2797.  I'd have concluded that this was NOT an
Intel board because of the non-Intel FDC, but the one board identifier I can
find says Intel.

I've got another '186-based board which uses a '286 as a processor and a
'186 as an I/O controller.  This one has ethernet, serial I/O, lots of RAM,
with "secded" and about 200 IC's on one side plus about a thousand passives
and discretes on the other.  It's from "Little Machines."

Dick
-----Original Message-----
From: Joe &lt;rigdonj(a)intellistar.net&gt;
To: Discussion re-collecting of classic computers
&lt;classiccmp(a)u.washington.edu&gt;
Date: Friday, May 28, 1999 9:37 AM
Subject: Re: Multibus-I Users ??

...
 Dick,

  I don't have any catalogs that show the single board computers but I
found something in the '85 Intel product guide.  It lists an iSBC 186/03
that has an 80186 and that they classify as both a CPU card and Mass
Storage Controller. There is only a one line description for each so I
don't know if it has 8042 or not. Here's the info that the CPU section
gives: CPU = 80186, RAM = 0 to 64K EPROM or EEPROM = 0-512K, iSBX expansion
connectors = 2, MultiMode Expansion = iSBC 341, Operating System Software =
iRMX. Here's what the mass storage section says: No. of boards = 1,
Interface Supported ="SCSI-single host environment (transfer rate 1.2
Mbyte/sec asynchrous)", No. of drives supported = "single targer
environment", S/W Support = RMX 86.  There is also a chart showing the year
of introduction and relatve performance. It was introduced in 1984 and it's
performace is a 5.

   Joe

At 07:30 AM 5/28/99 -0600, you wrote:
>Are there any users of the old Multibus-I out there?  I'm having difficulty
...
 >identifying a board that is so "busy"
that there was no room on which to put
...
 >an identifier in the silkscreen.  It's a FD/HD
controller with a '186 and an
...
 >8042 on it.  Sound familiar?
>
>Dick
>
>-----Original Message-----
>From: Richard Erlacher &lt;edick(a)idcomm.com&gt;
>To: Discussion re-collecting of classic computers
&gt;&lt;classiccmp(a)u.washington.edu&gt;
>Date: Thursday, May 27, 1999 11:16 PM
>Subject: Re: Re[4]: Bringing up a CPM
>
>
>>Yes, '81 was pretty late . . . CP/M-86 came out then, as did PC-DOS.
>>Within a few years, nobody wanted to be limited by the same systems they
>>coveted only a few years earlier.  By '81, the Apple][ could be equipped
>>with a Z80 board, a "real" FDC (Sorrento Valley Associates ?) an 80x24
>>display, and a hard disk if you could afford it.  I recently sold the
>>prototype of the original Apple HDC I made up in the spring of '81
together
...
 >>with my first ST-506.
>>
>>Those were the days . . . <sigh>
>>
>>Today I can still run CP/M but at an effective clock rate of 83MHz on my
>>notebook . . . designing hardware involves thousands of lines of HDL, weeks
...
 >>in front of a simulation, and when it's
done, I can't even hook up an
>>instrument small and fast enough to inspect it because even our government
...
 >>can't afford one.  One has to design
circuits with 25% overhead so they can
...
 >>be inspected.  Oh, well . . .
>>
>>Dick
>>-----Original Message-----
>>From: Allison J Parent &lt;allisonp(a)world.std.com&gt;
>>To: Discussion re-collecting of classic computers
&gt;&gt;&lt;classiccmp(a)u.washington.edu&gt;
>>Date: Thursday, May 27, 1999 8:54 PM
>>Subject: Re: Re[4]: Bringing up a CPM
>>
>>
>>><If you're writing your own, it might be well to keep in mind that the
>BIOS
>>><used in several late-generation CP/M systems used device drivers which
>>coul
>>>
>>>It was late generation in 1981!  I started doing it then.  CPM had a
>formal
>>>product called CP/M+ (CP/M3.0) to extend that idea.
>>>
>>><California Computer Systems (CCS) had a pretty nice boot process in
which
...
 >>><they loaded a skeletal BIOS in a 32K
CP/M, since 32K was the smallest
>>memor
>>><in which they claimed they could run.  It wrote that to the boot
blocks,
...
 >>>
>>>Actualy it was 20k for cpm2.2, as it was distributed as a 20k system
that
...
 >>>you would run movcpm on to get the xxK
version you wanted.
>>>
>>><then, under the control of that skeletal system, they loaded a
>"full-size"
>>><(you get to define that!) CP/M and transfer control to it.   It's
pretty
...
 >>><solid and makes the preparation of a
bootable disk a straightforward if
>no
>>><a quick process.
>>>
>>>Yes and they were doing it a long time back, Compupro too.  Kaypro was
one
...
 >>>of the few "boxed" system that
had the rom mapped to get a large TPA.
>>>
>>><IIRC, the XEROX 820 used a swapped-in BIOS which lived in PROM and was
>>><mapped into the TPA during file transfers, or something on that order.
>If
>>>
>>>Classic.
>>>
>>><your machine can handle that, it saves on BIOS size, especially tables,
>>etc
>>><and, generally speaking, if the READ operations from the TPA are from
>>><temprorarily mapped-in PROMs, you can overwrite the TPA in the event
>you'r
>>><loading overlays, with complete impunity.  That way your
>>blocking/deblockin
>>><buffer space can still reside in high memory.
>>>
>>>An IMSAI can neither handle that nor not handle that.  The basic design
>>>had no rom!  To do that you need a prom card with a little bit of
hardware
...
 >>>to map it with an IO port.
>>>
>>>The key here is to get a working system in whatever space... Why, it's
the
...
   >development platfrom for itself.  Once you have it
running and can poke and
  understand
it the improvements will come.

Allison