The last 12 months I have been pretty busy working on my 1410 in FPGA
project, and there is now more to share, though I have not done much
actual work since February - been too busy playing with other "toys". 8D
First, I finished working through all of the IBM 1410 and IBM 1415
Automated Logic Diagrams - generating VHDL and testing the results with
test benches. [Note that this includes the built-in 1401 compatibility
mode, activated at the flip of a switch.] That took most of 2020.
So, the CPU generation in VHDL is now more or less complete, and I added
a hand coded memory module for memory, as core is kind of hard to find
on an FPGA development board. ;) I am currently using a Digilent Nexys
4, but I think it might have even fit on a Nexys 2 - there is plenty of
room to spare, and there isn't anything in the VHDL aside from, maybe,
the memory implementation (though even that is pretty generic VHDL).
With this the CPU runs, at the very least, Unconditional branch (Jump),
Halt, NOP and Set Word Mark instructions seemingly correctly - I haven't
tried any others. Somewhat surprisingly, aside from issues with the
hand coded VHDL in triggers and the need to communicate pins tied to
logic one or zero, the auto-generated VHDL works untouched.
I have updated the github repository for the C# database application
that generates the VHDL from time to time (and which includes the
complete database) at http://github.com/cube1us/IBM1410SMS
There is now a *new* repository, http://github.com/cube1us/IBM1410FPGA
which holds the generated VHDL, some hand coded VHDL modules for certain
SMS cards (typically for triggers, for example), the console and test
benches I used along the way, and VHDL "Integration Tests" which are
designed to be loaded onto the board - the current one being
IntegrationTest3.
There will be, eventually, a third repository which will contain the C#
code that "hosts" the IBM 1410 console and peripherals, communicating
with the FPGA over a high speed serial over USB connection. I figured
out that this should allow me to emulate peripherals without having to
resort to sending data over Ethernet, SPI, I2C or the like. I have just
started that, so it really isn't at a point that there is much to share.
Once I have a console working (which will require a re-do of the console
VHDL implementation, which right now communicates in ASCII, but should
probably be using BCD), I should be able to pre-load into memory some of
the CPU diagnostics, by loading a diagnostic routine into either my 1410
simulator (http://github.com/cube1us/1410), or Richard Cornwell's
emulator in SimH and then taking a snapshot of "core" to pre-load into
the FPGA. At that point I expect I will be able to test the CPU pretty
thoroughly. I hope and expect that will happen this year sometime.
Unfortunately, I do not have the ALDs (Automated Logic Diagrams) for the
IBM 1414 I/O Synchronizers, but I do have the Instruction Logic Diagrams
which should allow me to code VHDL to emulate card, tape and maybe
eventually even disk functions, so those might take a while.
If anyone cares.... ;)
JRJ
Hi Josh,
Among the pictures linked from your message about the H742a parts, there is one picture of you backplane. I have been looking for some time for information about the following 11/45 ECO:
> KB11-00001 CODE: D May-72 [ECO]
>
> Problem: Etch carrying +5V current from Mate-n-Lock pins to backpanel pins is not heavy enough to carry required current. Correction: Run 24AWG wire in parallel with etch on panels which already have Mat-n-Lock assembly installed. Increase thickness of conductor with solder bead if Mate-n-Lock assembly not installed. PDP-11/45 system serial number 101 and later.
The wiring arrangements at the top of your backplane look to be a bit different from mine, and I believe you may have this ECO implemented. While you have your backplane out, could I ask that you take some closeups around the Mate-n-Locks along the top? I'd be very interested to see the board traces and the details of the red bus wiring there.
Pictures of the toasted 11/45 suggest that the original machine had the older power wiring scheme (distribution panel mounted vertically on back of cabinet instead of horizontally at top of cabinet, etc.) although your KB11A serial number badge is >2000, which is curious...
I sent Josh pictures of the complete RF08/RS08 that John Wilson donated to
the RICM. I will send detailed pictures of the RS08<->RF08 cables next week.
--
Michael Thompson
Hi folks,
Did anyone else get an email about excessive bounces today? I?ve not changed anything hosting wise forever so this is a bit weird.
Cheers,
--
Adrian Graham
Owner of Binary Dinosaurs, the UK's biggest private home computer collection?
t: @binarydinosaurs f: facebook.com/binarydinosaurs
w: www.binarydinosaurs.co.uk
Hi all --
In addition to the 11/45 project I'm also working on restoring an RF08/RS08
fixed head disk/controller (in the vain hopes of one day running TSS/8 on
my PDP-8/I). I have the power supply repaired and running and I'm getting
ready to power the logic up (the disc itself will be a project all its own,
once it arrives).
I'd like to double-check that all the flip chips are in their right places;
I have no cause to think they've been shuffled around but I want to be
sure. The engineering docs have detailed schematics but no placement chart
for the modules themselves. Given enough time with the schematics I could
derive this chart but I'm saving that as a last resort. So, two
possibilities here:
1) Does anyone know of a document I've overlooked that includes module
placement?
2) Can someone with an RF08 and/or RS08 take a few detailed pictures of the
logic (from the handle side, of course) so I can compare? (Note: the
available RF08/RS08 pictures on the 'net are of the unit currently in my
possession, so are not useful in this regard!)
Thanks!
- Josh
Spring cleaning. Will be recycled otherwise. While most are probably
not of interest to this group it's possible someone may want the SCSI
related items like the ES-1000C flatbed scanner manual or Yamaha
CRW8424SX manual or the Adaptec stuff.
I'm in downtown Toronto, Canada. On Freenode IRC my nick is genii
imgur gallery of the stuff https://imgur.com/a/USejVEv
--
"..we are dwarfs astride the shoulders of giants. We master their
wisdom and move beyond it. Due to their wisdom we grow wise and are
able to say all that we say, but not because we are greater than
they." Isaiah di Trani
> From: Eric Smith
> The KB11-B (original 11/70) and KB11-C (later 11/70) have essentially
> the same changes as from the KB11-A to KB11-D
Speaking of which, two of the boards that are different in the KB11-D, from
the -A, are _identical_ to boards in the KB11-C - the M8123 ROM & ROM control
and the M8132 instruction register decode! (The M8123 is also different from
the M8133 board in the KB11-B.) Pretty wierd that the -11/45 and -11/70 CPUs
share two boards, but true! (The FP11 boards are the same in both, too.)
> It sure would be nice to get backplane wirelists for all four (KB11-A,
> -B, -C, and -D).
ISTR a previous, un-fulfilled request for the -11/70 wirelist, so it's been
missing for a while.
We _might_ have the -11/45 wirelist:
http://www.bitsavers.org/pdf/dec/pdp11/1145/1145_System_Engineering_Drawing…
but it's short (pp. 128-132), so maybe it's not complete)? Two other
print sets seem to have the same list:
http://www.bitsavers.org/pdf/dec/pdp11/1145/1145_System_Engineering_Drawing…http://www.bitsavers.org/pdf/dec/pdp11/1155/MP00039_1155vol1_Mar76.pdf
(pp. 45-49 and pp 131-135 respectively).
> Also, I'm looking for a Field Maintenance Print Set for the RH70.
Heh. I didn't see it online; the manual:
http://www.bitsavers.org/pdf/dec/unibus/CSS-MO-F-5.2-27_RH70_Option_Descrip…
is a CSS document, which makes no sense, because the CPU backplane is laid
out to have room for four, so it's an integral part of the /70 CPU - so why
is it a CSS product? Anyway, the print set listed there seems like it might
be a CSS thing, too.
I see that the CHM seems to have a set:
https://www.computerhistory.org/collections/catalog/102749003
so maybe Al will take pity on us and scan it!
I looked in my /70 print set, and although it contains all sorts of odds and
ends (including MJ11 prints - which kind of half makes sense, since that was
the only main memory option on early /70's), it doesn't have the RH70. (I
didn't see the MJ11 prints on BitSavers, so I was thinking I was going to
have to scan them, but on further looking I found them on deramp.com.)
Noel
> From: Henk Gooijen
> I have the M8120 and 4 M8121 boards (32kW bipolar RAM). It is a bit
> weird, but in the 11/55 are also two G114 boards (4kW MOS RAM), IIRC.
G114s? Those are the sense/inhibit module from the MM11-U/MJ11. Did you
mean G401s?
If so, one guess as to what happened there is that the machine used to have
two banks of MS11 Fastbus memory, one bipolar, and one MOS, and some of the
boards from the MOS bank (the memory control, and maybe some of the matrix
boards) got removed?
A KB11-[AD] can have two banks of MS11; the only type mixing allowed is that
one can be all bipolar, and one all MOS; within each bank they all have to be
the same. More here:
https://gunkies.org/wiki/MS11_Semiconductor_Memory_System
Interesting factoid: the M8110 and M8120 use the same etch. I'm not sure
quite what the difference is (the MS11-A MM doesn't say, I couldn't find, and
I don't think we have the M8120 engineering drawings, just the M8110);
the M8120 has a bunch of ECO wires on it, and maybe there are component changes
too. (I don't have an M8110 to compare them directly.)
Noel