test-drb August 2016

test-drb@ccmp.vtda.org

175 participants
281 discussions

by vintagecomputer＠bettercomputing.net

So I have the 6800 almost fully working, however I've hit one snag. ? I loaded some of the memory diags as a first test, from txt files posted online. ?The first couple worked ok, but the third kept hitting an error immediately on start. ? I thought little of it and was eager to try a bigger program. ?I tried Blackjack. ?However I noticed when it was loading.. instead of just the cursor remaining beside my L until loaded, it began dumping random stuff out. So that's when I went back to that RAM test. ?I noticed it has having the same issue with a certain range. ?I realized then that my single RAM board was only covering from (I think) A000 up to but not including C000.? So I used the jumpers on my DRC 16k boards to fill in the blanks, so to speak. ?But I'm stuck on the last one. ?The memory check now crashes at address 8000. ?Because my last MPM board was modified, I'm not sure how to get that particular range. ?I'm also wondering why I only get from A000 to C000 on my other MP-M board. ?The 16k boards can be set for wide ranges.. say 8000 through I think FFFF (can't look at the docs as SWTPC.COM went down tonight). ?I'm assuming the smaller RAM boards cover less? ?With three of the four installed, I can load a program via txt file without error but cannot run it.. if I hit G it just freezes there. ?So I'm not sure if I need to configure a ram board for $8000 up to $A000 or if I potentially have another problem. ?And because the MP-M boards are both modified.. I don't know what they are/were set up to do. Brad Sent from my Samsung device

10 years, 1 month

TRS-80 Trash Talk - Live Episode

by COURYHOUSE＠aol.com

be sure to send a reminder right before too! sounds great! I never owned one in the old days but cure saw them around and we do have them at SMECC museum project in the collection. In a message dated 8/7/2016 9:01:17 A.M. US Mountain Standard Time, pete at pski.net writes: https://www.facebook.com/events/1044642265619305/

10 years, 1 month

ISO: HP 110 AC Adapter

by derschjo＠gmail.com

Hey all -- Picked up some lovely junk at the VCF consignment table today, amongst which was an HP 110 with carrying case, floppy drive, thinkjet, and manuals (including the service manual!). Not included was a means to power this thing up. Anyone have a power supply going spare? (Maybe even someone coming to VCF tomorrow? :) Thanks as always, Josh

10 years, 1 month

Mall directory computers

by vintagecomputer＠bettercomputing.net

Been wondering about this for a while. Just one of those odd childhood memories. When I was a kid growing up in Oakville, Ontario, I remember Oakville Mall getting one of those very early mall directory computers. This would have been like, 1982-84, somewhere thereabouts. From what I remember, they had kind of CGA-sh graphics and a chiclet 'keyboard' you used to browse the directory. I'm wondering, were they just PCs, most likely? Or some kind of custom job?

10 years, 1 month

SWTPC 6800

by vintagecomputer＠bettercomputing.net

I've definitely got an MP-B. What I'm thinking is I'll use one of the socketed 16k boards and go through the RAMs to make sure I have good. ?But I'm having trouble understanding how to set the jumpers to get the addressing to A000. ?I thought I had that by the guide for the ram on the swtpc site (it's a Digital Research board). ?The machine only gets animated when that weird piggybacked mpm board is plugged in. I suppose if there are bad RAMs on the DR board that'd do it though. Brad Sent from my Samsung device -------- Original message -------- From: Chris Elmquist <chrise at pobox.com> Date: 2016-08-06 7:10 AM (GMT-08:00) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: SWTPC 6800 Simplifying the machine configuration can help too.? You should only need MP-A (CPU), MP-S (serial interface) and MP-M at $A000 if you have the SWTBUG ROM.? It only needs 128 bytes of RAM at $A000 so an unexpanded (4K) or partially populated MP-M would be sufficient. If you have MIKBUG, then you need MP-C instead of MP-S since MIKBUG does not know how to talk to MP-S. Removing all the other cards temporarily could eliminate conflicts due to addressing, failed components, etc. With this minimal configuration, you should be able to get SWTBUG's "$" prompt.? MIKBUG will prompt with "*". Also, check which backplane board you have.? Depending on vintage, you may have MP-B or MP-B2.? MP-B2 allowed the I/O block address (normally at $8000) to be changed.? If you have MP-B2 and someone has customized the machine, then there will be more to figure out regarding where the I/O is really located, what the monitor ROMs expect, etc. http://www.swtpc.com/mholley/MP_B/MP_B_Index.htm http://www.swtpc.com/mholley/MP_B2/MP_B2_index.htm Chris On Friday (08/05/2016 at 10:47PM -0700), Brent Hilpert wrote: > Do you have some RAM at $A000+ yet? > That's all that should matter as far as required RAM goes. > > Presuming this is the holley page you were referring to: > http://www.swtpc.com/mholley/HiTerm/Test6800_Index.html > he does mention RAM needed at A000 for the BUGs, as Chris and I have been saying. > > Without RAM there there's no stack for return addresses for subroutines executed in the BUGs, so execution could head off to wherever. > > > On 2016-Aug-05, at 10:23 PM, Brad H wrote: > > Okay so.. I decided to try the MP-C board out, just for kicks.? No change. > > Then I decided to add one of the RAM boards.. the next one up in addresses.? Got a little bit when I powered on.? Added one of the old MPM boards.. one that has memory chips all piggybacked on one another.? Now when I powered up, the system was sending four or five characters at a time, linefeed, four or five characters at a time, linefeed ad infinitum.? I added the final MPM board.. zero. > > So.. I think we do have some ram problems.. most likely.? I'm thinking it would be easiest to concentrate efforts on the socketed RAM boards.. test all the RAM out.? I'm going to read up on addressing and try to understand a bit better what is going on.? I'm thinking maybe I need to reconfigure the addressing on one of the boards to match whatever that overstuffed MPM board is set to. > > Until I get an oscilloscope.. fooling around is about all I can do here. > > > > Sent from my Samsung device > > > > -------- Original message -------- > > From: Chuck Guzis <cclist at sydex.com> > > Date: 2016-08-05? 3:55 PM? (GMT-08:00) > > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > > Subject: Re: SWTPC 6800 > > > > On 08/05/2016 02:15 PM, Brad H wrote: > >> I think I will have to figure out how to do that.? Additionally I > >> have one of those PC based oscilloscopes on the way.? I don't know > >> how to use them 100% but I'm about to learn I guess. :) > >> > >> I have one more question for you guys -- I have a few CT-1024 > >> terminals and would really like this system to work with one of > >> those.? However, all of the CTs are quite delicate and are set I > >> think for 7, E, 2 @ 110 baud via soldered jumpers.? I'm a bit > >> reluctant to try pulling them apart to get in there and fix that.? Is > >> there a way to change the parity, etc settings on the SWTPC to match > >> the terminal?? Is it necessary? > > > > Well, 110 bps is a bit on the slow side--great for teletypes, not so > > much for video terminals.?? But you'll have to change the hardwired > > jumpers--the UART used in the CT1024 is not software-programmable. > > > > If this were my unit, I"d probably solder some pins into the pad holes > > and then either use slide on jumpers or wirewrap to set the > > characteristics.? That way, when changing things around, you won't be > > stressing the PCB. > > > > Something like this: > > > > http://www.ebay.com/itm/10PCS-20CFemale-to-Female-1-Pin-Plug-Jumper-Cable-W… > > > > Search on "female jumper wires" -- Chris Elmquist

10 years, 1 month

Yard sale goodies

by glen.slick＠gmail.com

On Aug 6, 2016 2:12 PM, "Joe Giliberti" <starbase89 at gmail.com> wrote: > > Greetings! > Went to a sale this morning and ended up with some neato pieces of > equipment. First are two Shugart 8 inch floppy drives ($1 each), a > microprocessor training kit ($30) and finally a RCA COSMAC dual 8 inch disk > drive ($5). One of the sellers told me to come back tomorrow because he's > going to dig out a bunch of other 70s and early 80s equipment. > https://postimg.org/image/gyjd3j16p/ > I can find no reference to either the microprocessor trainer for the cosmic > disk drive assembly online. Any information would be pretty cool to see. > > Thanks! > Joe Giliberti Those ICS microprocessor trainers show up on eBay from time to time. Erik has a page about them here. http://www.vintage-computer.com/ics.shtml

10 years, 1 month

VCF West - going?

by COURYHOUSE＠aol.com

surprised no one pulled off a live stream of this... In a message dated 8/6/2016 12:09:58 P.M. US Mountain Standard Time, billdegnan at gmail.com writes: Bruce Damer speaking now...incredible exhibits very talented exhibitors. .. hard to say what's "best"...taking lots of photos Bill Degnan twitter: billdeg vintagecomputer.net On Aug 6, 2016 11:51 AM, "Fritz Mueller" <fritzm at fritzm.org> wrote: > I'm headed down from Oakland now (Sat) and will be there most of the > afternoon. Looking forward to seeing all the goodies and meeting some > folks!

10 years, 1 month

TU56 Tape Heads

by michael.99.thompson＠gmail.com

During our PDP-12 debugging today we found that the left tape head has an open coil for data track 0. The left head was OK a little more than a year ago when we found the open coil in the right head. One TU56 head on my personal PDP-8/e also had an open coil when I got it. Our guess is the chemicals from the epoxy potting, possible flux residue, and poor soldering are causing the failures. Getting the epoxy potting out to repair the solder connection has proved impossible so far. Any source for three TU56 tape heads would be appreciated. We are also interested in ideas on how to get the epoxy potting out without destroying the head. -- Michael Thompson

10 years, 1 month

Somewhat amusing Grauniad article on retrieving old digital material

by lproven＠gmail.com

Germaine Greer's archive: digging up digital treasure from the floppy disks Archivists trying to preserve material stored in obsolete formats face a mighty challenge in retrieving decades of work by the Australian writer and feminist https://www.theguardian.com/books/2016/aug/05/germaine-greer-archive-digita… -- Liam Proven ? Profile: http://lproven.livejournal.com/profile Email: lproven at cix.co.uk ? GMail/G+/Twitter/Flickr/Facebook: lproven MSN: lproven at hotmail.com ? Skype/AIM/Yahoo/LinkedIn: liamproven Cell/Mobiles: +44 7939-087884 (UK) ? +420 702 829 053 (?R)

10 years, 1 month

VCF West - going?

by vintagecomputer＠bettercomputing.net

Is anyone shooting video for those of us that can't go? ?I really enjoyed the videos of VCF East I found on Youtube. ?I'll likely never get to one of these things being up here in Canada.. still fun to check out virtually. Brad Sent from my Samsung device -------- Original message -------- From: Curious Marc <curiousmarc3 at gmail.com> Date: 2016-08-05 3:03 PM (GMT-08:00) To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Subject: Re: VCF West - going? I'll be there with some of my HP equipment. On my way there soon. Marc Sent from my iPad > On Aug 5, 2016, at 10:08 AM, Ian Finder <ian.finder at gmail.com> wrote: > > I'll be there. Flying down from Seattle after work with an Amiga 4000 060 > and a GRiD in my carry-on. > I wanted to bring a Symbolics machine, but they happen to be quite heavy. ;) > > On Fri, Aug 5, 2016 at 10:01 AM, william degnan <billdegnan at gmail.com> > wrote: > >> I am here now, will be around all day helping set up.? I have not been to >> the CHM since the last VCF...The space for the event looks good, tables are >> out and waiting for exhibitors. >> >>> On Fri, Aug 5, 2016 at 12:07 PM, Josh Dersch <derschjo at gmail.com> wrote: >>> >>> On Thu, Aug 4, 2016 at 12:25 PM, Ali <cctalk at ibm51xx.net> wrote: >>> >>>>> I am heading to VCF West after a stop over in San Fran today...I am >>>>> looking forward to meeting up with everyone.? I will be there all day >>>>> Friday as a set-up volunteer, Sat and Sunday morning.? I was at the >>>>> last VCF before it was called "West" ... it's been too long. >>>> >>>> I am going to be there both days and look forward to meeting people In >>>> Real Life (TM). So should the list members get special badges or >>> something >>>> so people can know who is who? Or *GASP* are we going to have to be >>>> personable and talk to each other! :D >>>> >>>> -Ali >>> I'll be there co-running the Living Computer Museum's exhibit.? Stop by >> and >>> say hi! >>> >>> - Josh >> >> >> >> -- >> @ BillDeg: >> Web: vintagecomputer.net >> Twitter: @billdeg <https://twitter.com/billdeg> >> Youtube: @billdeg <https://www.youtube.com/user/billdeg> >> Unauthorized Bio <http://www.vintagecomputer.net/readme.cfm> > > > > -- >?? Ian Finder >?? (206) 395-MIPS >?? ian.finder at gmail.com

10 years, 1 month

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test-drb August 2016