test-drb September 2016

test-drb@ccmp.vtda.org

162 participants
227 discussions

by useddec＠gmail.com

The following is a partial list of things I plan on bringing to VCF tomorrow. I plan on being there by noon, and will return home Saturday night. If you have any interest, flag me down. If I have time I?ll try to grab some 8 boards. Thanks, Paul M3106 DZQ11 M3107 DHQ11 M7081 LA120 LOGIC BOARD M7504 DEQNA M7546 M7677 11/84 M7846 RX11 M7940 DLV11 M7944 MSV11-B M7946 RXV11 M7955 MSV11CD M7957 DZV11 4 LINE M8012 BDV11 M8013 RLV11 M8014 RLV11 M8015 KPV11-A M8017 DLV11-E M8021 MRV11-BA M8027 LPV11 M8029 RXV21 M8043 DLV11-J M8044 MSV11-DD M8053 DMV11 M8959F 64K M8059K128K M8067F 64KW M8067 128KW M8186 11/23 CPU M8189 11/23+ CPU M8190-A KDJ11-BF M9047 GRANT G7273 GRANT PDP8-E no cards VT52, untested 2 computer automation naked minis-never used mini 4 9 full cards can't see model of the other one, but i think it is a 4 or 5 card 2 motorola M-4408 NIB, bought new from Carroll Touch, a local company that made early touch screens for plato. Nova 3 no boards, nice clean Kennedy 9610, very clean

8 years

WTB: GRiDcase 3 screen or entire GRiDcase 3 or 1520 with small plasma for parts

by ian.finder＠gmail.com

Mine just died, an entire row driver went out. I just bought this thing! :( -- Ian Finder (206) 395-MIPS ian.finder at gmail.com

8 years

Unicomp Minicomputers [WAS: RE: Components available]

by t.gardner＠computer.org

See http://bitsavers.informatik.uni-stuttgart.de/pdf/unicomp/UNICOMP_Brochure_19 70.pdf Unicomp became Spectra Data became Gilmore Industries and then ??? Art worked for Unicomp Tom -----Original Message----- From: Mark J. Blair [mailto:nf6x at nf6x.net] Sent: Thursday, September 08, 2016 2:50 PM To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: Components available I am not at all familiar with Unicomp minicomputers, and I'd love to see pictures of this one. I'm sorry that I'm not closer to the machine, but it sounds like heroic rescuers are already lined up to keep it from getting scrapped. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/

8 years

TK50 with DEC All-in-1

by curt＠atarimuseum.com

Hi Anyone have a TK50 install of this ? Either for sale, trade or loan? Thanks, Curt

8 years

AS400 Model 170 potentially available...

by lbickley＠bickleywest.com

Weirdstuff has been offered an AS400 Model 170 located in a data center. If anyone is interested in purchasing it, let me know off list - please include the approximate price you'd be willing to pay for the critter. I'll pass your info on to Weirdstuff so they can decide whether to make a bid on it or not. Note: I am not affiliated with Weirdstuff other than as a paying client. They don't like to see vintage gear scrapped anymore than I do. Regards, Lyle -- 73 AF6WS Bickley Consulting West Inc. http://bickleywest.com "Black holes are where God is dividing by zero"

8 years

Y Combinator is restoring one of Alan Kay's Xerox Alto machines

by curiousmarc3＠gmail.com

> > On Sep 5, 2016, at 9:30 AM, Josh Dersch <derschjo at gmail.com> wrote: > > > > At the LCM, I used an Apple II to test out the Alto's memory -- the > > Alto II XM uses 4116 RAM chips. I swapped in a row at a time and wrote a > > little BASIC program to test for obvious errors. This was > > time-consuming, but eliminated the obviously bad chips, which helped immensely. > > Oh, that's so simple and clever! Are these 16k chips? I don't have an Apple II, > but I wonder if I could use the same trick and plug them in my HP 85 > for which I just managed to burn the service ROM, which has a memory > test built in. Josh, I checked, and the mysterious HP 1818-1396 or 1818-0341 RAM chips used in the HP-85 appear to be NEC uPD416-2 or MOSTEK 16k chips. They appear to be pin for pin, voltage and speed compatible with the MOSTEK 4116-3 used in the Alto. So it looks like I could check the Alto Xerox II-XM RAM chips on my HP-85. 8 at a time, that might take a while :-). Thanks for the tip, I'd never have thought about it! Marc

8 years

Q-Bus Memory Diagnostics and Repair

by jnc＠mercury.lcs.mit.edu

> From: Jerry Weiss > I'll give that a try. Please let us know how you make out with it! :-) > I've been making do with the SMS 1000 manual for the basic settings as > well. Yeah, that's better than nothing. I just looked over my notes from looking into the CMV-x000, and alas I don't have any useful data to report (yet). > I ran a different diagnostic w/o parity testing enabled. That's kind of odd; the top block of results make it look like it's dropping the 0400 bit (e.g. "S/B", which I assume means 'should be', = 161612, and "WAS" = 161212 makes it sound like it dropped the 0400 bit); but the block below makes it look like it's picking that bit (it shows 0 and 0400 under the S/B and WAS columns for that location). Eh, no biggie; clearly the 0400 bit has issues! ;-) > I see stuck bits and address decoding problems. It looks like some > memory addresses return the contents of another address. Not sure I see that happening? If your CPU is an 11/73 (which can directly 'access' [hate that verbism :-] all of memory from ODT, unlike the 11/23 which is restricted to the bottom 256KB), try playing around with a failing location, and its alternative, directly, and see if a store of random data into one can be read back directly >from the other; e.g. set 03561212 to 0, store 0123456 in 03561612, and then try reading 03561212, etc. Then go back to 03561612 and see if you get 0123456 back when reading it. Etc, etc. That should quickly verify if the problem is just some locations which drop/pick bits, or if there are addressing issues. > I may just clip the power lead on the chip I think is faulty to confirm > I have the correct target. I looked at my CMV-x000 boards, and on all of them, the chips are soldered in, not socketed (which most of the other ones I looked into had, which made working out the chip<->bit tables very easy - pull random chips, and see what happened :-). But your proposed move should let you identify if you have the right chip. Once done, you might want to check low memory from ODT to make sure you don't have the banks inverted (i.e. what looks like the top bank is not in fact the bottom). It probably wouldn't boot the diagnostics, if so, but it'd nice to find out directly! > Hopefully the bit ordering matches the board marking and bottom row is > the highest address of memory banks. Please let me know what the layout is, and I'll start the Computer History wiki page for this board with that info. Noel

8 years

Q-Bus Memory Diagnostics and Repair

by jnc＠mercury.lcs.mit.edu

> From: Jerry Weiss > The first is an MSV11-PL 512KB-Q-Bus 22bit. > Dead to both CSR and Memory address access in ODT. > ... before start poking around with my scope ... can recommend a > particular methodology to finding the fault. Well, the CSR and RAM address detection circuits are separate (page 5 of 11 in the drawings), so since both are not responding, it has to be something in common: perhaps something on the input side like a bus receiver (e.g. BSYNC, pg 8), perhaps something on the output side like a control line driver (e.g. BRPLY, same page), or some of the common circuitry that drives it (e.g. TRPLY generation on pg. 5). The way to tackle this is to write a two instruction loop that reads the CSR (that will be easier to grok than RAM access); it will need a NXM trap catcher which just does an RTI, too; and don't forget to set up the SP. Then, pick some likely point half way along the signal path (e.g. MSEL, on the right hand edge of pg. 5), and see if that's doing what it should. If no, start moving back upstream; if it is OK, start going downstream from there. > The second board is a CMV1000 that probably has a bad Memory Chip. > I don't have either prints or a manual for this board. Yes, either/both for this, and the sister CMV4000 (same board with 256K chips) would be really fantastic to locate. I'm in the process of working out what all the jumpers/mean do, and will work out which chips correspond to which bits, and document them, like this page: http://gunkies.org/wiki/CMV-504 However, we're not there yet for this card, so... > I was expecting bad and xor to be 16bit values, but they appear to be > mostly 22bit addresses. But then again this isn't a DEC board. That shouldn't make a difference. I can't make head or tail of the output either; can anyone else help? (I don't use DEC diagnostics, I have rolled my own PDP-11 memory diagnostic.) > The board itself is labeled with bits 0-7 P0 P1 8-15 across the top Well, that is a good hint... :-) > Any suggestions as to which chip might be suspect? Step A is to find out what the failing location(s) are, and what the bad data is. So either figure out the DEC memory diagnostic output, or roll your own (you can have mine if you like, I have Unix assembler source, or I can give it to you in .LDA binary). Noel

8 years

Components available

by t.gardner＠computer.org

Hi A friend of mine died recently; he was amongst many things an electronics tinkerer and has a closet full of small parts in bin cabinets (resistors, capacitors, ICs, transistors, hardware, etc.). The ICs look mostly old. His wife and kids have no interest and would like to find a good home for these parts rather than recycle the lot. They are in Palo Alto CA Anyone interested in using them could just pick them up in the next week or so. Any other ideas? Really hate to see these go to recycle. Tom (650) 941-5324 <tel:%28650%29%20941-5324>

8 years

{wtb} DEC VT100 5 spoke rolling stands

by smj＠ma.sdf.org

I'm looking for a couple DEC VT100 5 spoke rolling table stands. Please contact me privately if you have one available. Thank you

8 years

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test-drb September 2016