test-drb

test-drb@ccmp.vtda.org

101090 discussions

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

MicroVax II update

by dj.taylor4＠comcast.net

Progress on getting the MVII up and running: I ordered the SCSI2SD adapter and it has come in, the plan is to use it as the system disk on the MVII. The hobbyist VMS PAKS have arrived and I was able to download the VMS 7.3 iso, not sure what I can do with it since I think it must be burned to a 512 byte sector CD. I asked if the PAKS were good for older versions of VMS, like 5.5, and was told yes they were. We'll see about that. The Hobbyist VMS CD I had for VMS 7.2 was found and I was able to get the old Toshiba CD drive to work on the MV 4000 using a CQD 223A. How can I create an image of these CD's on the VAX 4000 that I could use in an emulator? I wasn't able to get the UC07 to see the CDROM because of a bad SCSI cable, I had hoped to format the SCSI2SD using the UC07. Is it possible to use the SCSI2SD on a microPDP-11 under RT-11? I ask because of the disk size limit under RT-11. Doug

10 years, 1 month

IBM Diskette OEM Information manuals wanted

by spacewar＠gmail.com

Does anyone happen to have the IBM Diskette OEM Information manuals: GA21-9190 one-sided GA21-9257 two-sided I'm specifically NOT looking for the Diskette General Information Manual, GA21-9182, unless someone has an edition earlier than Fourth or later than Sixth. The OEM Information manuals were the definitive reference for the track formats for eight-inch diskettes. Generally equivalent information is available from a lot of later sources, including ECMA, ISO, and ANSI standards, and from vendor datasheets and application notes for floppy drives and floppy disk controller chips, though I've encountered a number of inaccuracies in vendor documentation. The ECMA standards are available online. I'm interested in the IBM OEM information manuals primarily for historical reasons, not because I'm missing any particular technical information. Thanks! Eric

10 years, 1 month

How to get a Heathkit H8 to work with a serial terminal

by dkelvey＠hotmail.com

Hi Note that the combo card does not work reliably above 4800 baud. It feeds the serial through an optical isolator, even when doing RS232. It is really intended to do current loop at lower speeds. Dwight ________________________________ From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Bill Sudbrink <wh.sudbrink at verizon.net> Sent: Monday, August 1, 2016 6:01:21 PM To: 'General Discussion: On-Topic and Off-Topic Posts' Subject: RE: How to get a Heathkit H8 to work with a serial terminal Try in the SEBHC group: sebhc at googlegroups.com

10 years, 1 month

[IBM1130] 029 keypunch available

by ball.of.john＠gmail.com

Make this yet another person as well in BC who would be jumping on it . I got almost no use for a card reader if I have no way to punch the cards. >Ditto. I'd be all over that if I wasn't in BC.

10 years, 1 month

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test-drb