18 May
2015
18 May
'15
4:55 p.m.
Eric Smith wrote on 5/17/2015 9:34 PM:
I have two dumps of 8041 code from two different systems. One was a
model 220 and the other was a 230. All I know is that the images are
different from each other. I didn't record the part number. (I created
those files about 25 years ago...) If you know that there were only two
versions released, by some strange chance, then one of these must be it.
But I just checked my parts bin and I have two IOC boards (not
completely functioning I think) that have that 104566-001 part. When I
get a chance I can create an image, assuming I can get my eprom burner
to run. It worked when I put it away. Just hoping the gremlins haven't
taken it.
I made two or three RPC86 boards from SBC-86/12 boards. It wasn't very
easy. There were lots of wire jumpers and a few cut foils. There was a
special PAL chip. And, of course, the firmware. So I have the firmware
(or at least I have the EPROMS) for the RPC86. To create the PAL I was
able to copy the code from an authentic RPC86 as Intel hadn't burned the
protection fuse. I carefully documented all the jumpers and cut foils
and used that documentation to make my second and third RPC86. I will
look for the firmware code for you. But I probably won't get to it right
away. Summer is here and I want to scuba dive and shoot at targets
while the weather cooperates. :)
I sent out your Single Density ISIS-II 4.3 boot diskette today with
Kermit on it. It is my customization of Kermit that detects whether it
is running on an MDS or a PDS and uses the correct I/O ports. I find it
most reliable at 2400 bits/second.
On Sun, May 17, 2015 at 6:06 PM, Dave Mabry <dmabry
at mich.com> wrote:
One of the enhancements in the iMDX-511 was a fast block write to the
crt. I'd bet that write to arbitrary IOC memory has something to do
with that. It was about the time that Intel released ALTER (later
renamed AEDIT) which was a very nice screen oriented text editor. If
you had the 511 installed it did very fast screen writes.
As for the firmware, there were many versions.
At one point Intel released
an upgrade package called the iMDX-511. That added cursor-addressbility on
the integral CRT, a function key on the keyboard (replaced the RPT (repeat)
key), some shortcut key sequences, improved speed, and other things I can't
remember. It was a standard part of the Series-II at some point, about the
same time the white one became available.
I've dumped all the programmable
parts from a Series II with an IPB
(8080 main CPU board) and the IOC iMDX-511 firmware, except the IOC
8041A and a few soldered-in bipolar PROMs used for address decode on
the IPB. My firmware images are on Bitsavers:
http://bitsavers.trailing-edge.com/pdf/intel/MDS2/firmware/mds2.zip
I have all that rom code. I even took a swipe at
disassembling it to try to
understand it. That was never finished, but I did make some progress.
As have I.
I found that the IOC firmware has undocumented 0dh and 0eh
commands. Command 0x0d allows the main CPU to write to arbitrary IOC
memory, and is probably for diagnostics, but is not allowed unless IOC
RAM location 5af4h contains the value 24h, and I haven't figured out
how that can be made to happen, since you can't use command 0x0d to
set it if it isn't already set. I haven't yet figured out what
command 0eh does. If the
8741/8041 chip on the IOC was called the PIO (Parallel I/O) then I
have that rom code too. I have a document that says the 8041 is indeed the
PIO.
Yes. I'd like a copy. Can you confirm that the one you dumped is P/N
104566-001? The iMDX-511 also included an enhancement to the
keyboard processor. I have
that rom code as well.
104675-001, included in the ZIP file on bitsavers.
Do you have dumps of the firmware for the RPB86 and/or RPC86 8086 CPU
boards used in the Series III?
Best regards,
Eric