test-drb December 2008

test-drb@ccmp.vtda.org

209 participants
286 discussions

by dave06a＠dunfield.com

Hi Guys, I've been contacted by a chap in Maryland with a Borroughs B80 he wants to find a home for - I don't think he wants anything for it other than shipping cost if non-local. Too big/far for me ... if anyone is interested, please contact me for his info. Regards, Dave -- dave06a (at) Dave Dunfield dunfield (dot) Firmware development services & tools: www.dunfield.com com Collector of vintage computing equipment: http://www.classiccmp.org/dunfield/index.html

15 years, 4 months

Bootstrapping the oldest VAXen (was Re: 4.3BSD Quasijarus)

by ethan.dicks＠gmail.com

On Tue, Dec 30, 2008 at 12:14 AM, Bob Armstrong <bob at jfcl.com> wrote: >> Glen Slick wrote: >>I basically followed along with the installation info I found here and >>gettting a basic bootable system installed was fairly straight >>forward. >> >>http://www.itsecuritygeek.com/itsgeek/comments/43bsd-quasijarus-on-simh-vax Nice. > This procedure is for a MicroVAX, though. You're not going to be able to > boot directly from magtape on a 11/7xx VAX. If you already know this (or still have the battle scars yourself), what we did back in the day, for installs, we booted 9-track tapes on PDP-11s (RK05 or RL02 if you didn't have tape, but the media charge was expensive), TK50s or RX50s on early MicroVAXen, and "console media" for large VAXen. The 11/78x models had RX01s via the internal PDP-11 console processor, the 11/725 and 11/730 had TU58 by the internal 8085 console "processor", the 11/750 came right up via ROM and could boot TU58s, and ISTR the 86xx had RL02, but I don't know by what attachment. You had to order your OS with the right console media to be able to boot up a "standalone restore" program which was then used to (sometimes) prep the disk and to restore the first saveset off of, commonly, a 9-track tape. Early on, VMS might have been small enough to fit on console media entirely, but by the time I was doing it (VMS 4.x), we had a tape and a pack of TU58s for our 11/750. Our UNIX distros (System III, 4BSD...) always came on magtape. I still have a pile of TU58s from our 11/750, but when I went to read them off a few years ago, I did not achieve 100% for any tape set. If anyone would still have a stack of VMS install floppies for a 11/78x, I think those might be more robust and quite possibly still legible. What I can't recall is how hard it is (i.e. - how manual and how much esoteric knowledge you have to have at your fingertips) to make a standalone restore kit once you have a running system. Eventually, and I forget when it started, you could create a VMS "SYSE" directory structure on your system disk for standalone backup with a provided script, but that doesn't help you get a completely bare machine up and running. This aspect of VAXen has hampered me now and then over the years - there's a lot of little fiddly software bits you have to have for installs and complete recoveries - stuff you never need when the machine is working fine. Unfortunately, I don't think I have everything we did when I did this every day or I'd have more working machines. It appears, looking back on things, that a long-term advantage of the MicroVAX architecture was that they did _not_ have console processors, so they had to be able to boot any MSCP device, so disks and diskettes and tape interfaces all were designed to fit the bill. The 11/7xx line does _not_ have that advantage, so takes more resources to bootstrap from the factory-fresh state. So if anyone who has resources from before 1995 (VMS before 6.0 or older versions of Ultrix or 4BSD) wants to write me off-list, I think there's a need to pull out what we all might have to see what combinations of systems and operating systems we can cover. With the present state of simh, it seems that the 11/780 is the way to go (there was a recent thread on the simh mailing list about this sort of thing and I think it's safe to say that emulation of other 11/7xx machines is distant or worse). Unfortunately for me, I don't happen to have *any* 11/780-specific resources, but I do have plenty of OS magtapes, etc. from about 1985-1995, FWIW, and quite a few 11/750 and 11/730-specific resources since that's what we had then. *Is* anyone on the list sitting on a pile of ancient OS install kits? If so, have they been read into disk and tape image files already? -ethan

15 years, 4 months

T-11 (was Re: PDP-11/70 cache memory)

by ajp166＠bellatlantic.net

> >Subject: T-11 (was Re: PDP-11/70 cache memory) > From: "Ethan Dicks" <ethan.dicks at gmail.com> > Date: Mon, 29 Dec 2008 19:21:07 -0500 > To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> > >On Mon, Dec 29, 2008 at 5:52 PM, Gordon JC Pearce MM3YEQ ><gordonjcp at gjcp.net> wrote: >> Alexandre Souza wrote: >> >>> The SBC6120 is a **real nice** SBC... > >Yes it is, and it's back in "print"! > >> ... [I] wish I had saved a T-11 (was it?) >>> processor from many of the arcade boards I saw going to trash...I do not >>> even know how to operate a PDP, but it would be something fun to learn :o) > >T-11s aren't terribly rare. Perhaps not as common as other 40-pin >CPUs from the 1980s but they can be found on DEC boards and in at >least one DEC terminal. The issue of using one in a modern >SBC6120-like board has been brought up from time to time, and one of >the limitations I think I recall is that they don't have a MMU and, >unlike the F-11, there wasn't one for it, severely limiting your OS >choices. Between that and it not being simple to emulate DEC >interfaces down to the CSR level, turning a T-11 into a bootable >PDP-11 isn't easy at all. Making a 64KB board that runs PDP-11 >instructions isn't hard - but then what do you do for software? It's >a harder problem to solve than on the PDP-8 since there really is only >one dominant OS there (plus a lot of OS-less paper-tape software). >Writing _a_ disk driver for one OS for your new disk (such as with the >SBC6120) isn't a terrible obstacle. For the PDP-11, you have to >consider that folks would be interested in RT-11, RSX, RSTS, and >several varieties of UNIX. > I have a few T-11s and they are fun to play with. The bare T11 will run RT-11 without mmu. The real problem is you need DL serial (or fake it) and also a disk otherwise you have to build your own drivers. The VT24x terminals used it and they actually implmented the basic PDP11 MMU to get 18 bit addressing. the parts load to do that is not steep but it didn't have the memory protection half of the MMU. >The T-11 would make a fun little board if you happen to know or want >to learn the PDP-11 instruction set and have a use in mind for some >configuration smaller than a console line and a disk/disk emulator. > In this day and age a disk would best be a SD or maybe CF part fewer parts and easier to bring up. >> I think I asked the question a couple of years ago, about which "classic" >> non-typical CPUs turned up in arcade machines. I seem to recall someone >> saying that the T-11 was used in Paperboy. > >Yeah... I remember reading about the T-11 in Paperboy some time back >and was quite surprised. Large quantities of video games spanned the >progression over the years from 8080 to Z-80 and 6809 to 68000 as >complexity and sound and color advanced, and there were a few games >here and there with something odd like a 6502, but the rare appearance >of a T-11 really stood out for me. I never played Paperboy much, and >I haven't seen too many of the machines in the wild since I learned >they hid a T-11 inside. > One of the few non industrial or DEC designs that did use it. Allison >-ethan

15 years, 4 months

compugraphic on ebay UK

by rogpugh＠mac.com

Merry christmas, happy new year all. Spotted this on Ebay UK in case its of interest to anyone. its listed in the wrong category so may not appear on everyones radar. Item no. 180317075811 roger

15 years, 4 months

Z80 CTC, DART, & PIO system clock question

by lynchaj＠yahoo.com

Hi! I am building a Z80 peripheral for an ECB bus device. All the Z80 control, data, and address bus signals are present on the ECB bus. However, the system clock (4MHz) signal is not available. The Z80 peripheral data sheets mention a "standard Z80 single-phase system clock" input to the CTC, DART, and PIO. I would like to supply a "local" 4MHz TTL oscillator can as an input to the CTC, DART, and PIO chips. Obviously, the "local" oscillator will not be exactly in phase or synchronized with the CPU clock. Do the Z80 peripherals require *the* CPU system clock or *a* system clock? I believe it is *a* system clock but do not know for sure and the documentation is not clear enough for me to tell. This is what the documentation says regarding the CTC Clock(phi) System Clock (input). This single-phase clock is used by the CTC to internally synchronize certain signals. If anyone knows *definitively* (not speculation) whether a "local" oscillator can serve as the CTC, DART, & PIO system clock and still work with the SBC CPU over the bus please let me know. Responses to this thread or send to my email. Thank you in advance Andrew Lynch

15 years, 4 months

Heathkit manuals under tighter control

by jfoust＠threedee.com

http://techdirt.com/articles/20081215/0106043118.shtml - John

15 years, 4 months

WTB: Sony SMC-70G Software, Peripherals, Manuals, Etc.

by Apergy＠aol.com

Please contact me directly at _apergy at aol.com_ (mailto:apergy at aol.com) . Happy New Year, Randy In a message dated 12/29/2008 11:06:25 A.M. Eastern Standard Time, cctalk-request at classiccmp.org writes: Send cctalk mailing list submissions to cctalk at classiccmp.org To subscribe or unsubscribe via the World Wide Web, visit http://www.classiccmp.org/mailman/listinfo/cctalk or, via email, send a message with subject or body 'help' to cctalk-request at classiccmp.org You can reach the person managing the list at cctalk-owner at classiccmp.org When replying, please edit your Subject line so it is more specific than "Re: Contents of cctalk digest..." Today's Topics: 1. Re: Suggestions for VT103? (Ethan Dicks) 2. Re: Suggestions for VT103? (Jerome H. Fine) 3. Re: [SPAM] - Re: Suggestions for VT103? - Sending mail server found on dnsbl.sorbs.net (Jerome H. Fine) 4. Re: Suggestions for VT103? (Jerome H. Fine) 5. Re: Suggestions for VT103? (Jerome H. Fine) 6. Re: Suggestions for VT103? (Jerome H. Fine) 7. Re: Suggestions for VT103? (Doc Shipley) 8. RE: Heathkit manuals under tighter control (dwight elvey) 9. Re: Suggestions for VT103? (Sridhar Ayengar) 10. uIEC/SD == AWESOME! (Zane H. Healy) 11. Re: Jupiter Ace - PCBs and such (Dave McGuire) 12. Re: uIEC/SD == AWESOME! (Jim Brain) 13. Re: Suggestions for VT103? (Ethan Dicks) 14. Facit 4431 terminal (Johnny Billquist) 15. Re: 4.3BSD Quasijarus (der Mouse) 16. ACCRC Sealed-Bid Auction Lot #2 Ready (Sellam Ismail) 17. Re: Jupiter Ace - PCBs and such (Alexandre Souza) 18. Re: 4.3BSD Quasijarus (Sridhar Ayengar) 19. Re: Suggestions for VT103? (Diane Bruce) 20. Re: Suggestions for VT103? (Sridhar Ayengar) 21. Re: Suggestions for VT103? (Diane Bruce) 22. Re: uIEC/SD == AWESOME! (Zane H. Healy) 23. MK11 with 1MB boards (Johnny Billquist) 24. PDP-11/70 cache memory (Johnny Billquist) ---------------------------------------------------------------------- Message: 1 Date: Sun, 28 Dec 2008 21:26:24 -0500 From: "Ethan Dicks" <ethan.dicks at gmail.com> Subject: Re: Suggestions for VT103? To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <f4eb766f0812281826r1374d1a3j84fc51b93785b4a7 at mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 On Sun, Dec 28, 2008 at 9:07 PM, Sridhar Ayengar <ploopster at gmail.com> wrote: > Ethan Dicks wrote: >> >> What you are after is rosin-core lead-based solder around 60/40 or >> 63/37 tin/lead, with a diameter around 0.5mm (.020") to 0.8mm (.032"). > > I highly recommend 63/37 over 60/40. I find it easer to work with. Sure, but I'd never _not_ do a project because all I had on hand was 60/40, though. -ethan ------------------------------ Message: 2 Date: Sun, 28 Dec 2008 21:36:29 -0500 From: "Jerome H. Fine" <jhfinedp3k at compsys.to> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <495837AD.2060707 at compsys.to> Content-Type: text/plain; charset=us-ascii; format=flowed >Tony Duell wrote: >I refuse to beleive it takes you over an hour to solder one connection! :-) > > Jerome Fine replies: Well, maybe soldering a VT103 backplane was not so bad, but I seem to remember the problems I once had with a DRV11 module. It needed to be strapped, but the only way that DEC provided to change the CSR value was with zero ohm resistors. Removing a strap just meant cutting out a resistor. But I found it impossible to add a resistor. Finally after several hours of unsuccessful attempts (and almost damaging the board), I solved the problem by removing a few male connector pins from a damaged board and soldering them into the appropriate holes where the zero ohm resistor leads would normally be placed. Since the very tiny pin was easy to manipulate and could be easily inserted into a melted solder hole, I ended up with two pins which I could them wire wrap since the pins were very similar to wire wrap posts in the first place. Why DEC had not done that to start with I don't know, but I finally did change the CSR value. And it took about TWO hours each to finally insert each pin. Needless to say, I am not a bit fan of making solder connections at this point. >>As far I my experience is worth, the upgrade to a 22 bit backplane with >>the version DEC >>provides in the VT103 works VERY well. I watched over at least 6 VT103s >> >That does not suprise me. I was under the impression that some very early >Q-bus modules used at least one of those pins for something else (I've >seen 3rd-party Q-bus cards with 22 bit DMA capability where the bus >driver for thsoe upper 4 address lines (normally a '38 or similar) is >socketed with instructions to remove it if used in certain backplanes) >but I suspect the VT103 is late enoguh for this not to be an issue. > > As far as I know, the LSI-11 CPU modules (both dual and quad) do use some of those address lines. But the M8186, M8189, M8190 and M8192 can't since they all support 22 bit addresses for memory. So the VT103 backplane from DEC with 18 bit address lines probably supports the use of the LSI-11 CPUs, but not after modification to 22 bit addresses. Since the PDP-11/73 CPUs are now readily available, I can't see anyone using an LSI-11 CPU at this point except in VERY unusual situations which require the LSI-11 CPU for a special reason - like the microcode which can be modified. I don't know of anyone who ever modified the microcode for an LSI-11 CPU. That is not to say that I will not invent new PDP-11 instructions such as an UNSIGNED multiply, 32 bit multiply and divide which will be implemented under Ersatz-11. But as the fellow in Irma La Duce said "That is another story." >>The really cool reason to use a VT103 is that a hard drive can be placed >>right under the CRT. >> >I wonder about stray magnetic fields from the yoke and/or flybackj >transformer. Not that they'll corrupt the magnetic patterns on the disk, >but that they'll be picked up by the read amplifier anf cause random data >erros. But I guess it works OK. > > Not knowing about stray magnetic fields, I just put an ST412 (actually a DEC RD51) under the tube and started to run. This used a Sigma RQD11-B MFM controller (dual board with boot ROMs) with an M8186. Worked great. Made them available to Ontario Hydro as a work station. Since they were already using the VT103 with a dual RX02 floppy drive, the hard drive was a huge improvement. They ran RT-11 and having a 10 MByte hard drive rather than a 0.5 Mbyte floppy made a huge improvement. Expensive at the time, but worth while for commercial use. >>The one problem of using the VT103 is that the power supply is really >>too limited, although with >>only 4 slots, not a lot of power needed. Tony, perhaps you might be >>able to suggest how >>the 5 amp supply could be enhanced? On the other hand, with a BA23 >> >> > >Do you mean '5 amp' or '5 volt' here? I was under the impression it was >around 15A or so at 5V. > > Yes! I did mean the 5 Volt which is limited to 16 Amps on the VT103. And that includes all of the boards, including the VT100 video card and anything else in the VT100 which uses the 5 Volt level. >Increasing the rating of a PSU is not easy in general. Many of the >components would need replacign with higher-rated parts, including the >transformer (whether linear or switch-mode), the rectifiers, smoothing >capacitors (increase in capacitance value), chopper transistors (if an >SMSPU), pass transistors (if a linear design), etc.and of course you'd have >modify any current limit circuitry. It'd probably be easier to design a >replacement PSU from scratch to fit in the same space. > > I thought as much. I will continue to use the BA23 and BA123 for now. Since the core 2 duo CPU runs Windows XP which runs Ersatz-11 which runs RT-11 at more than 100 times the speed of a PDP-11/93, it is not likely that I will be using a real DEC CPU much in any case. By the way, with SATA II drives, the disk I/O is probably 200 times faster than any ESDI or SCSI drive connected to a PDP-11. >>As for modes of failure, how often should a power supply be used to be >>sure that keeping it out >>of service does not cause a failure when the power supply is used after >>a few years? Does anyone >>have any recommendations? >> >About the only thing that'll fail from not being used are electrolytic >capacitors, and I am not convinced this is a major problem with >modern-ish ones. Certainly it's not a failure I've ever encountered (yes, >I've had electrolytics fail, but not by the oxide-film disolving due to >them not being used). > I probably turn on the PDP-11/83 about 2 times a year. Since I had 2 BA123 power supplies fail in the past 10 years, I wondered about having to use them or loose them. At one point, I was told by a company that I did some software programming for that their major customer required them to run the PDP-11 systems every 3 months until delivery which was not to be for 2 years. Thus the reason for my question. Sincerely yours, Jerome Fine ------------------------------ Message: 3 Date: Sun, 28 Dec 2008 21:37:02 -0500 From: "Jerome H. Fine" <jhfinedp3k at compsys.to> Subject: Re: [SPAM] - Re: Suggestions for VT103? - Sending mail server found on dnsbl.sorbs.net To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <495837CE.9070208 at compsys.to> Content-Type: text/plain; charset=us-ascii; format=flowed >Josh Dersch wrote: > >Glen Slick wrote: > >> http://www.bitsavers.org/pdf/dec/terminal/vt103/MP00731_VT103_Aug80.pdf >> >> Page 73 of 76, VT103 BACKPLANE > > So forgive my inexperience here -- but just to make sure I'm > understanding the changes I need to make -- is all that's necessary > just wiring up the address lines (18-21) from slot 1, to slot 2, to > slot 3, to slot 4? Jerome Fine replies: Don't forget that both ABs in each slot need to be wired in since each quad slot can hold 2 dual boards. That means a total of 8 solder joints for each address line and a total of 32 solder joints for all 4 address lines. Very fine insulated wire wrap seems to be a good solution. The plastic insulation can be stretched after each solder joint is made to cover the wire right up to the solder joint. A wire stripper can be used to custom cut the insulation at the exact spot needed - cut a bit short and stretch the insulation after the solder is cold. Then daisy chain from slot to slot as needed. Start with the first solder joint with about 2" of free wire, then custom cut the insulation to the correct length for the second solder joint on the same slot (second AB on that slot). It probably helps to keep the wires as neat as possible since the next address line is very close. > Also, just to satisfy my curiosity -- it's been mentioned by several > people that lead-based solder is necessary -- why is this? (I think I > have a spool of it somewhere that I liberated from my grandfather's > basement some years back, but I'll have to dig it up...) Ethan answered this much better than my limited knowledge! Sincerely yours, Jerome Fine ------------------------------ Message: 4 Date: Sun, 28 Dec 2008 21:38:02 -0500 From: "Jerome H. Fine" <jhfinedp3k at compsys.to> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4958380A.2040204 at compsys.to> Content-Type: text/plain; charset=us-ascii; format=flowed >Josh Dersch wrote: > I have a number of RQDX3's, but I'll probably go with the Emulex QD21 > ESDI controller that I have. It has an auto-boot option, which will > be useful since the 11/23 board I have just has the ODT ROMs... Jerome Fine replies: I use a Sigma RQD11-EC quad ESDI controller which can run 4 ESDI drives. What I like best is that 3 drives are VERY easily (just ground the correct line) made WRITE PROTECTED. Not having a proper panel, I just use a 10 pin cable and alligator clips to ground the line. The Hitachi DK515 with about 600 MBytes each work well. I modified the RT-11 MSCP device driver to allow me to boot any of the 60 partitions on the 3 drives. Normally, I use 3 drives with 2 being backups and only drive 0 with 20 RT-11 partitions being modified at any time. All drives are usually WRITE PROTECTED most of the time since I normally fix bugs in the RT-11 operating system and the device drivers. Since any mistakes in my code modifications could corrupt the hard drive, having them hardware WRITE PROTECTED prevents that until I have checked out the code. After I have made the changes to the backup drives, I boot the backup drive and copy the changes to drive 0 which is now just a data drive. I have 2 command files which compare all 20 partitions on drive 0 to each of the 20 partitions on drive 1 or drive 2. That takes about 4 minutes for each pair of RT-11 partitions of 32 MBytes each or about 80 minutes in total. Under Ersatz-11 with a core 2 duo, it takes about 1.7 seconds per pair of RT-11 partitions of 32 MBytes or about 30 seconds for all 20 pair of RT-11 partitions - not even time to get a drink. I am working on enhancing the HD: device driver under Ersatz-11. It is twice as fast as the MSCP device driver. For raw throughput, if I bypass the HD: device driver code and use a user subroutine without interrupts (hardly necessary when things are this fast), making a copy of an RT-11 partition of 32 MBytes is twice as fast again. A straight copy is about 0.2 seconds for all 32 MBytes as opposed to about 240 seconds the copy an RT-11 partition on those very fast (for a real DEC PDP-11/83 system) ESDI hard drives. Sincerely yours, Jerome Fine ------------------------------ Message: 5 Date: Sun, 28 Dec 2008 21:39:02 -0500 From: "Jerome H. Fine" <jhfinedp3k at compsys.to> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <49583846.4070900 at compsys.to> Content-Type: text/plain; charset=us-ascii; format=flowed >Ethan Dicks wrote: >>On Sun, Dec 28, 2008 at 5:20 PM, Josh Dersch <derschjo at mail.msu.edu> wrote: > > >>Also, just to satisfy my curiosity -- it's been mentioned by several people >>that lead-based solder is necessary -- why is this? >> >> > >Because the equipment was made with lead-based solder (being many, >many years older than the RoHS directives), and mixing lead-free and >lead-based solder is not a good idea. I'm sure someone here can quote >chapter and verse, but AFAIK, you'll get unreliable solder joints if >you try. > > > >>(I think I have a spool >>of it somewhere that I liberated from my grandfather's basement some years >>back, but I'll have to dig it up...) >> >> > >If that's plumbing solder, you are unlikely to get good results. >Really, really old plumbing solder _is_ lead-based, but most of what >you are likely to find is not (so that it's safe to use on supply >lines). Plumbing solder is also frequently acid-cored or fluxless. I >don't recall running into any plumbing solder that is compatible with >electronic circuits. > >Now...if your grandfather was a Ham or did electronic repairs, what >you have might be just perfect, but be sure you have the right stuff >before you get started. > >What you are after is rosin-core lead-based solder around 60/40 or >63/37 tin/lead, with a diameter around 0.5mm (.020") to 0.8mm (.032"). > The exact ratio of lead to tin is not critical, nor is the exact >diameter, but since you aren't doing ultra-fine work or trying to >solder down something huge and heavy, like bundles of power-supply >leads or RF cages, I'd recommend something "medium" weight, like the >0.8mm (.032"). > >There should be a label on one end of the spool (if it's still on the >original spool) describing the various characteristics. If you aren't >practiced at making good joints, I'd recommend getting an inexpensive >electronic hobby kit to practice on. My earliest efforts from when I >was in Jr. High are rather ugly - by the time I was adding blue wires >to $2000 boards at work five years later, I'd gotten much, much better >from the early practice. > > Very helpful - thank you! Sincerely yours, Jerome Fine obtained by replacing the four characters preceding the 'at' with the four digits of the current year. ------------------------------ Message: 6 Date: Sun, 28 Dec 2008 21:42:57 -0500 From: "Jerome H. Fine" <jhfinedp3k at compsys.to> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <49583931.4090103 at compsys.to> Content-Type: text/plain; charset=ISO-8859-1; format=flowed >Jerome H. Fine wrote: [Snip] Sorry about the subject line - my son modifies it when his server thinks it is something suspect. > >Josh Dersch wrote: > >> >Glen Slick wrote: >> >>> http://www.bitsavers.org/pdf/dec/terminal/vt103/MP00731_VT103_Aug80.pdf >>> >>> Page 73 of 76, VT103 BACKPLANE >> >> >> So forgive my inexperience here -- but just to make sure I'm >> understanding the changes I need to make -- is all that's necessary >> just wiring up the address lines (18-21) from slot 1, to slot 2, to >> slot 3, to slot 4? > > > Jerome Fine replies: > > Don't forget that both ABs in each slot need to be wired in since each > quad slot > can hold 2 dual boards. That means a total of 8 solder joints for > each address line > and a total of 32 solder joints for all 4 address lines. > > Very fine insulated wire wrap seems to be a good solution. The > plastic insulation > can be stretched after each solder joint is made to cover the wire > right up to the > solder joint. A wire stripper can be used to custom cut the > insulation at the exact > spot needed - cut a bit short and stretch the insulation after the > solder is cold. Then > daisy chain from slot to slot as needed. Start with the first solder > joint with about > 2" of free wire, then custom cut the insulation to the correct length > for the second > solder joint on the same slot (second AB on that slot). It probably > helps to keep > the wires as neat as possible since the next address line is very close. > >> Also, just to satisfy my curiosity -- it's been mentioned by several >> people that lead-based solder is necessary -- why is this? (I think >> I have a spool of it somewhere that I liberated from my grandfather's >> basement some years back, but I'll have to dig it up...) > > > Ethan answered this much better than my limited knowledge! > > Sincerely yours, > > Jerome Fine ------------------------------ Message: 7 Date: Sun, 28 Dec 2008 21:53:23 -0600 From: Doc Shipley <doc at mdrconsult.com> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <495849B3.6020708 at mdrconsult.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sridhar Ayengar wrote: > Ethan Dicks wrote: >> What you are after is rosin-core lead-based solder around 60/40 or >> 63/37 tin/lead, with a diameter around 0.5mm (.020") to 0.8mm (.032"). > > I highly recommend 63/37 over 60/40. I find it easer to work with. I had the dubious distinction of being a "Certified Solder Operator" for TI's Lubbock, TX plant (in, what, '82?). Although the training I got there spoiled me forever in some ways, it's been invaluable over the years. One of the things that stuck was the "true purpose" of eutectic solder. We always used 60/40 for original or initial soldering, and eutectic for repairs or "oversolders". If you have a good iron and a good eye (or, these days, good Optivisor), the flow-point difference allows doing new work without disturbing old joints. Doc ------------------------------ Message: 8 Date: Sun, 28 Dec 2008 20:04:44 -0800 From: dwight elvey <dkelvey at hotmail.com> Subject: RE: Heathkit manuals under tighter control To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <COL107-W56ACC5C91959AB0F1EED01A3E60 at phx.gbl> Content-Type: text/plain; charset="iso-8859-1" ---------------------------------------- > Date: Sun, 28 Dec 2008 19:58:00 -0600 > To: cctalk at classiccmp.org > From: jfoust at threedee.com > Subject: Heathkit manuals under tighter control > > > http://techdirt.com/articles/20081215/0106043118.shtml > > > - John > Hi Technically, if you have a H89 or such and you've lost the manual, you have a right to a copy of the manual without paying any copyright fee. The manual is already payed for. Still, if they have the copyright, they can have it removed >from the web if they can prove it is used for anything other than replacing lost manuals. I'm no lawyer and this is just a personal opinion. Dwight _________________________________________________________________ Life on your PC is safer, easier, and more enjoyable with Windows Vista?. http://clk.atdmt.com/MRT/go/127032870/direct/01/ ------------------------------ Message: 9 Date: Sun, 28 Dec 2008 23:10:19 -0500 From: Sridhar Ayengar <ploopster at gmail.com> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <49584DAB.1000500 at gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Ethan Dicks wrote: > On Sun, Dec 28, 2008 at 9:07 PM, Sridhar Ayengar <ploopster at gmail.com> wrote: >> Ethan Dicks wrote: >>> What you are after is rosin-core lead-based solder around 60/40 or >>> 63/37 tin/lead, with a diameter around 0.5mm (.020") to 0.8mm (.032"). >> I highly recommend 63/37 over 60/40. I find it easer to work with. > > Sure, but I'd never _not_ do a project because all I had on hand was > 60/40, though. Oh no, that's not what I'm saying at all. It's just that, if I'm going to be buying lead solder, I'll buy 63/37 every time. Peace... Sridhar ------------------------------ Message: 10 Date: Sun, 28 Dec 2008 21:24:08 -0800 From: "Zane H. Healy" <healyzh at aracnet.com> Subject: uIEC/SD == AWESOME! To: classiccmp at classiccmp.org Message-ID: <p06240800c57d8d8ad10d(a)[192.168.1.199]> Content-Type: text/plain; charset="us-ascii" ; format="flowed" The uIEC/SD I bought from Jim Brain was delivered Friday night (USPS was actually unable to deliver for several days in our area). My mail is currently going to a different location than we're living, so I picked it up yesterday, and retrieved my customized C64 from storage, and got everything plugged in last night (this was the first time we'd been able to get our car out of the driveway in over two weeks). Once I figured out how to use it, all I can say it is seriously cool, way better than my MMC-Replay for dealing with D64 images, and it was a lot cheaper! I'm even able to use it with the MMC-Replay plugged in so I have my Ethernet connection. With the MMC-Replay I was only able to get one or two D64 images to work, with the uIEC most I've tried have worked. I've been playing "Temple of Apshai" all day and having a blast! :-) Now to decide if I put it in some sort of case, or if I mount it inside the C64 somehow. Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh at aracnet.com (primary) | OpenVMS Enthusiast | | MONK::HEALYZH (DECnet) | Classic Computer Collector | +----------------------------------+----------------------------+ | Empire of the Petal Throne and Traveller Role Playing, | | PDP-10 Emulation and Zane's Computer Museum. | | http://www.aracnet.com/~healyzh/ | ------------------------------ Message: 11 Date: Mon, 29 Dec 2008 01:30:28 -0500 From: Dave McGuire <mcguire at neurotica.com> Subject: Re: Jupiter Ace - PCBs and such To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> Cc: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <36662B2D-068D-4CD9-B096-F1129A6CCCA3 at neurotica.com> Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed On Dec 28, 2008, at 6:02 PM, Phill Harvey-Smith wrote: >>> BTW I was given a bare unpopulated Ace board for Christmas, I >>> have taken some scans of it but at 1200dpi they are *HUGE* >> I'd be willing to turn those scans into Gerber files if you send >> them to me.. > > That would be cool, an eagle board layout would be better still..... > > Let me see if I can zip em up small, I'll prolly upload them to a > server at work (and email off list) as it has much more bandwidth > than I do and they are really huge :) I use PCB, not Eagle, (see http://www.geda.seul.org/) but getting them into SOME maintainable format would be better than nothing. -Dave -- Dave McGuire Port Charlotte, FL ------------------------------ Message: 12 Date: Mon, 29 Dec 2008 00:33:44 -0600 From: Jim Brain <brain at jbrain.com> Subject: Re: uIEC/SD == AWESOME! To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Cc: classiccmp at classiccmp.org Message-ID: <49586F48.3090205 at jbrain.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Zane H. Healy wrote: > The uIEC/SD I bought from Jim Brain was delivered Friday night (USPS > was actually unable to deliver for several days in our area). My mail > is currently going to a different location than we're living, so I > picked it up yesterday, and retrieved my customized C64 from storage, > and got everything plugged in last night (this was the first time we'd > been able to get our car out of the driveway in over two weeks). > > Once I figured out how to use it, all I can say it is seriously cool, > way better than my MMC-Replay for dealing with D64 images, and it was > a lot cheaper! I'm even able to use it with the MMC-Replay plugged in > so I have my Ethernet connection. With the MMC-Replay I was only able > to get one or two D64 images to work, with the uIEC most I've tried > have worked. I've been playing "Temple of Apshai" all day and having > a blast! :-) > > Now to decide if I put it in some sort of case, or if I mount it > inside the C64 somehow. > > Zane > > I'm glad you're enjoying it. As I implied in a previous post, the device has an interesting history that has shifted my philosophy concerning such projects. I've come to realize that, in the hobbyist space, collaboration yields much more fruit for the project, even though one loses the "I did it all myself" statement. I was always afraid I would never learn as much if I didn't do it all myself, but that has *NOT* been the case. And, it's nice to bounce ideas off others when trying to map new concepts like IDE partitions and such into a 25+ year old platform. Although I am now biased, I started uIEC because I felt the IDE64 took away too much flexibility. It assumes the 64 is the only CBM machine, requires an expansion port, and requires programs use only the normal KERNAL IEC routines if they are to work. As a VIC/C128 owner, that seemed wrong. The MMC64, on the other hand, is more complex to explain. As a "mega-cart", it's fine (load cart images onto SD card, play lots of cart or single filer games). But, then they started marketing it as a general purpose drive unit (or people started assuming it world work like that), I think it suffered. It's not ideally suited for that use. There are still things to do with the uIEC base, though. IEEE488 support would be a great win, as then PET/CBM machines would have a solid state device to use, and I am working on a USB link to a PC, so one can slave their Win/Mac/Linux box to their CBM. And, for those who want something more vintage as a target, the protocol is simple RS232 (I use a RS232->USB converter), so they could add a MAX232 and write a suitable app for anything that provides RS232. Jim ------------------------------ Message: 13 Date: Mon, 29 Dec 2008 02:02:47 -0500 From: "Ethan Dicks" <ethan.dicks at gmail.com> Subject: Re: Suggestions for VT103? To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <f4eb766f0812282302v60ff9f65pe8ca668b81520d10 at mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 On Sun, Dec 28, 2008 at 10:53 PM, Doc Shipley <doc at mdrconsult.com> wrote: >> I highly recommend 63/37 over 60/40. I find it easer to work with. > > I had the dubious distinction of being a "Certified Solder Operator" for > TI's Lubbock, TX plant (in, what, '82?). Although the training I got there > spoiled me forever in some ways, it's been invaluable over the years. Neat. I never had formal training - just practical tips and experience. Oh, wait... I _did_ get one training course - on how to do SMT benchwork when I was at Lucent... I worked on the plant floor for a couple of weeks. > One of the things that stuck was the "true purpose" of eutectic solder. We > always used 60/40 for original or initial soldering, and eutectic for > repairs or "oversolders". If you have a good iron and a good eye (or, these > days, good Optivisor), the flow-point difference allows doing new work > without disturbing old joints. Ah! I get it. Interesting. None of the stuff I've done was that finicky, but it's good to know. -ethan ------------------------------ Message: 14 Date: Sun, 28 Dec 2008 16:33:15 +0100 From: Johnny Billquist <bqt at softjar.se> Subject: Facit 4431 terminal To: cctalk at classiccmp.org Message-ID: <49579C3B.2040307 at softjar.se> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Anyone have any docs for this terminal? It's a plain glass terminal. VT100-compatible. I have a problem with mine, and don't have any kind of documentation. I do see that the data lines have junk on them, and the serial port isn't working. But internal tests pass, and the setup and local mode works fine. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol ------------------------------ Message: 15 Date: Sun, 28 Dec 2008 14:09:08 -0500 (EST) From: der Mouse <mouse at Rodents-Montreal.ORG> Subject: Re: 4.3BSD Quasijarus To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <200812281912.OAA13191 at Sparkle.Rodents-Montreal.ORG> Content-Type: text/plain; charset="iso-8859-1" > I guess all the people who still like to run them have SCSI > controllers on them by now, [...] I wish. I don't run my uV2, but that's largely because I don't have more than trivial quantities of disk that's compatible with the Qbus disk interfaces I have. At one point it looked as though I might get a Qbus SCSI card that wasn't bootable (I don't mind netbooting as long as I can _run_ off local disk), but that never actually materialized.... /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B ------------------------------ Message: 16 Date: Mon, 29 Dec 2008 04:20:57 -0800 From: sellam at vintagetech.com (Sellam Ismail) Subject: ACCRC Sealed-Bid Auction Lot #2 Ready To: cctalk at classiccmp.org Message-ID: <4958C0A9.mailH7I13DY3H at vintagetech.com> Content-Type: text/plain; charset=us-ascii Announcing: ACCRC Seald-Bid Auction Lot #2 *** This is the last notice that will be sent to the general VCF mailing list. To ensure you receive further updates regarding this auction, please visit the VCF website and click the "Mailing List" link in the navigation tab on the right-hand side or bottom of any page. Then click on the link to update your contact information and follow the prompts from there to get into your profile. You should then select which announcements you want to receive. If you don't want to receive any more of these auction notices, select "Major announcements and newsletter only". Otherwise, select "Send me all VCF announcements". The Alameda County Computer Resource Center (ACCRC) is forced to liquidate its computer museum due to the current economic climate. The VCF has been contracted to auction off the ACCRC museum to raise needed funds for their non-profit operation. I have put up the second batch of machines at the following URL: http://www.vintage.org/special/2008/accrc/ In order to use the system you must have a VCF Community ID. Getting one is simple: just follow the links and prompts when you visit the URL above and read the instructions. The closing time for this lot is Monday, January 5, at 12:00PM PST. New lots will be posted by noon every Monday on a weekly basis until all items are depleted. At this rate we expect 4-5 more lots. ACCRC Sealed-Bid Auction Lot #2 ## Description -- ------------------------------------------------- 16 Kaypro 2X 24 Kaypro 1 42 Eagle II 43 HP 41CV Calculator 44 JC Penny Video Sports 45 Timex-Sinclair 1000 46 Stratus V101 Dumb Terminal 47 HP 85 48 Tandy Color Computer 3 49 Calcomp Drawing Board 50 Atari 2600 Video Computer System 51 Tandy CCR-82 Computer Cassette Recorder 52 Generic Lunchbox Portable 53 Atari 830 Acoustic Coupler Modem + 850 Interface 54 Magnavox Odyssey2 Console 55 Commodore Amiga 500 56 GRiDPad 1900 57 Compaq Portable 58 Platinum Apple IIe 59 Processor Technology Sol-20 60 Non-Linear Systems Kaypro 10 Check the item listings at the link above for further information and details. All items must be sold. No reasonable offer will be refused. Your purchases will go towards supporting an organization that over the years has provided nearly 20,000 refurbished computers to needy organizations and individuals worldwide. 100% of the proceeds of this auction will go directly to the ACCRC (minus the handling fees, which are covering my time...barely). Best regards, Sellam Ismail Proprietor Vintage Computer Festival http://www.vintage.org ------------------------------ Message: 17 Date: Mon, 29 Dec 2008 10:48:36 -0200 From: "Alexandre Souza" <alexandre-listas at e-secure.com.br> Subject: Re: Jupiter Ace - PCBs and such To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> Message-ID: <08d001c969b3$d10c0c60$46fea8c0 at DeskJara> Content-Type: text/plain; format=flowed; charset="iso-8859-1"; reply-type=original > I'd be interested in how this is done as well. Lots of folks ask me to > reproduce vintage boards, and creating EAGLE CAD drawings for them is > time consuming. It is because eagle sux. A lot. :o) ------------------------------ Message: 18 Date: Mon, 29 Dec 2008 08:21:28 -0500 From: Sridhar Ayengar <ploopster at gmail.com> Subject: Re: 4.3BSD Quasijarus To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4958CED8.5050201 at gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed der Mouse wrote: >> I guess all the people who still like to run them have SCSI >> controllers on them by now, [...] > > I wish. I don't run my uV2, but that's largely because I don't have > more than trivial quantities of disk that's compatible with the Qbus > disk interfaces I have. > > At one point it looked as though I might get a Qbus SCSI card that > wasn't bootable (I don't mind netbooting as long as I can _run_ off > local disk), but that never actually materialized.... Why not cluster-boot with local swap? Shouldn't be too slow. Peace... Sridhar ------------------------------ Message: 19 Date: Mon, 29 Dec 2008 08:54:50 -0500 From: Diane Bruce <db at db.net> Subject: Re: Suggestions for VT103? To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Message-ID: <20081229135450.GA35079 at night.db.net> Content-Type: text/plain; charset=us-ascii On Sun, Dec 28, 2008 at 09:26:24PM -0500, Ethan Dicks wrote: > On Sun, Dec 28, 2008 at 9:07 PM, Sridhar Ayengar <ploopster at gmail.com> wrote: > > Ethan Dicks wrote: > >> > >> What you are after is rosin-core lead-based solder around 60/40 or > >> 63/37 tin/lead, with a diameter around 0.5mm (.020") to 0.8mm (.032"). > > > > I highly recommend 63/37 over 60/40. I find it easer to work with. > > Sure, but I'd never _not_ do a project because all I had on hand was > 60/40, though. As you know, the biggest difference is the lower melting point of 63/37, that does make it easier to work with. I don't suppose I need to say this, but never ever ever use the roll of solder your father used for plumbing with the acid core. Ever. > > -ethan > - 73 Diane VA3DB -- - db at FreeBSD.org db at db.net http://www.db.net/~db ------------------------------ Message: 20 Date: Mon, 29 Dec 2008 08:57:38 -0500 From: Sridhar Ayengar <ploopster at gmail.com> Subject: Re: Suggestions for VT103? To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4958D752.4040607 at gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Diane Bruce wrote: > On Sun, Dec 28, 2008 at 09:26:24PM -0500, Ethan Dicks wrote: >> On Sun, Dec 28, 2008 at 9:07 PM, Sridhar Ayengar <ploopster at gmail.com> wrote: >>> Ethan Dicks wrote: >>>> What you are after is rosin-core lead-based solder around 60/40 or >>>> 63/37 tin/lead, with a diameter around 0.5mm (.020") to 0.8mm (.032"). >>> I highly recommend 63/37 over 60/40. I find it easer to work with. >> Sure, but I'd never _not_ do a project because all I had on hand was >> 60/40, though. > > As you know, the biggest difference is the lower melting point of 63/37, > that does make it easier to work with. It's not the lower melting point. It's that the mixture is eutectic. Peace... Sridhar ------------------------------ Message: 21 Date: Mon, 29 Dec 2008 09:08:57 -0500 From: Diane Bruce <db at db.net> Subject: Re: Suggestions for VT103? To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org> Cc: General Discussion: Message-ID: <20081229140857.GB35079 at night.db.net> Content-Type: text/plain; charset=us-ascii On Mon, Dec 29, 2008 at 08:57:38AM -0500, Sridhar Ayengar wrote: > Diane Bruce wrote: > >On Sun, Dec 28, 2008 at 09:26:24PM -0500, Ethan Dicks wrote: > >>On Sun, Dec 28, 2008 at 9:07 PM, Sridhar Ayengar <ploopster at gmail.com> ... > >>Sure, but I'd never _not_ do a project because all I had on hand was > >>60/40, though. > > > >As you know, the biggest difference is the lower melting point of 63/37, > >that does make it easier to work with. > > It's not the lower melting point. It's that the mixture is eutectic. Yes I know it is eutectic. But for newbies the lower temperature is much easier on the board, one tends to lift fewer foils this way. It's also much easier with a decent soldering station to not lift foils, but if you don't have such, a lower melting point means the newbie tends not to overdo it. Of course, if you are soldering some heavy duty backplane, which I believe was the start of this thread, I suppose it's not as much of a problem. But I'd still recommend not using lead/acid solder for a backplane. ;-) > > Peace... Sridhar > - 73 Diane VA3DB -- - db at FreeBSD.org db at db.net http://www.db.net/~db ------------------------------ Message: 22 Date: Mon, 29 Dec 2008 07:59:00 -0800 From: "Zane H. Healy" <healyzh at aracnet.com> Subject: Re: uIEC/SD == AWESOME! To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>, General Discussion: Cc: classiccmp at classiccmp.org Message-ID: <p06240802c57e9ddce09f(a)[192.168.1.199]> Content-Type: text/plain; charset="us-ascii" ; format="flowed" At 12:33 AM -0600 12/29/08, Jim Brain wrote: >The MMC64, on the other hand, is more complex to explain. As a >"mega-cart", it's fine (load cart images onto SD card, play lots of >cart or single filer games). But, then they started marketing it as >a general purpose drive unit (or people started assuming it world >work like that), I think it suffered. It's not ideally suited for >that use. I'm glad I own a MMC-Replay cart, especially with the RRNET option, but if the uIEC had been available I might not of purchased it. While you can mount D64 images, you can't run most software from them. I think the situation might be better on PAL C64's. I've found that Individual Computers has a habit of advertising features that don't quite live up to my expectations. I also own a Catweasel card for my Amiga, and even though I bought it nearly 10 years ago, I'm still a bit ticked over it. If something doesn't include device drivers, you shouldn't advertise it as supporting various formats. It basically could read 2 of the floppy types it claimed to support. >to use, and I am working on a USB link to a PC, so one can slave >their Win/Mac/Linux box to their CBM. And, for those who want >something more vintage as a target, the protocol is simple RS232 (I >use a RS232->USB converter), so they could add a MAX232 and write a >suitable app for anything that provides RS232. If you support Mac & Linux this might be of interest to me. My major problem with just things has been the fact that it only ever seems to support Windows, and I don't typically have a Windows machine running. One question, what size SD cards does the uIEC support, and does it support HDSD cards? Right now I'm using the 2GB card from my MMC-Replay and it wants its card back. :-) Zane -- | Zane H. Healy | UNIX Systems Administrator | | healyzh at aracnet.com (primary) | OpenVMS Enthusiast | | MONK::HEALYZH (DECnet) | Classic Computer Collector | +----------------------------------+----------------------------+ | Empire of the Petal Throne and Traveller Role Playing, | | PDP-10 Emulation and Zane's Computer Museum. | | http://www.aracnet.com/~healyzh/ | ------------------------------ Message: 23 Date: Mon, 29 Dec 2008 12:35:28 +0100 From: Johnny Billquist <johnny.billquist at synap.se> Subject: MK11 with 1MB boards To: mcguire at neurotica.com Cc: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4958B600.50405 at synap.se> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Ok. To start with the short version. Get back when you really want more details. The deal is to fake the MK11 so that it thinks there are four 256KB cards when you have a 1MB card. The memory bus is pretty simple. You have address lines, and card select lines. Address lines are as usual. Card select lines are like chip selects, or whatever you are used to in terminology. It selects which card should respond when address and data and other control signals are on the bus. Usually only one card select line is active at a time. So you have three things to deal with: . Address lines . Card select lines . ECC Address lines are pretty simple. You grab four card select lines, hook a 4-to-2 binary multiplexor in there, and you get A18,A19 from those. This means that four adjacent cards will cause A18,A19 to be generated. Card select lines are even simpler. You just OR the four card select lines together, and output it on one of them. I seem to remember that you don't need to cut anything on the backplane, but check that to be sure. Also, you need a total of four of these special cards in order to get 4 MB working in the MK11, but all four cards will be identical. With that, the hardware side is done. Now, the one part left is a bit more tricky, but it's a hardware problem with a software solution. The MK11 (as well as the 11/750) have ECC memory. In order for the memory to not scream bloody hell when you access it, the syndrome bits must be set right. At power up, the MK11 initialize the syndrome bits for all memory in the box, but it does this in a really clever way. It runs though all addresses and do a write to them, forcing the ECC syndrome bits to be updated. *But*... It does this on all cards in the box in parallell. That is, all card select lines are active at the same time, at this one instance. The problem with that is that (obviously) not all the memory in the 1MB memory board will be reset. By designing your small adapter card the right way, you can get atleast the first 256KB ECC syndrome bits set right. The rest you'll have to do by software instead, before the memory can be used. Otherwise you'll just get parity errors if you try to access that memory. And, normal writes to memory won't work! The memory is 32 bits wide, and a normal write from a PDP-11 will only write 16 bits, so it won't cause the memory to do a blind write and just set the syndrome bits. If you read the documentation for the MK11, you'll find that it actually have a CSR as well, and in that, you can set bits to force writing the syndrome bits and ignore errors. And for the initialization that's what you need to do: set the right bits in the CSR, write to all memory needed, and then reset the CSR again. The last "funny" thing with this is that the CSR isn't easy to access. All accesses to the I/O page in an 11/70 will cause the reference to run out on the Unibus (not surprising). However, the MK11 isn't on the Unibus. :-) The trick is to realize that the Unibus map will always direct the access to the memory bus, even if the final address is in the I/O page. So, you need to setup the Unibus map to point to the I/O page, and then access the MK11 CSR through the Unibus map. After that, you're all done, and the MK11 with 1MB memory boards will be happy. I've done it in the past, and it really not any more complicated than that. Johnny ------------------------------ Message: 24 Date: Mon, 29 Dec 2008 12:52:14 +0100 From: Johnny Billquist <bqt at softjar.se> Subject: PDP-11/70 cache memory To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Message-ID: <4958B9EE.1050507 at softjar.se> Content-Type: text/plain; charset=ISO-8859-1; format=flowed And since some have mentioned it, there was a 3rd party upgrade to the 11/70 which replaced the whole memory system with a few cards in the CPU box, which turned all memory into cache. This was by a company called SETASI, and the product was the hypercache. They actually had two products. HC-70 was the hypercache, and then you had something called the PEP-70 as well. It appears they could be used together, but I don't know if one was required for the other, or if they were related in any way, and if so how. (SETASI also did other stuff, such as a SCSI adapted for massbus, which was pretty nice, and usable both on 16-bit and 36-bit machines.) Johnny End of cctalk Digest, Vol 64, Issue 65 ************************************** **************One site keeps you connected to all your email: AOL Mail, Gmail, and Yahoo Mail. Try it now. (http://www.aol.com/?optin=new-dp&icid=aolcom40vanity&ncid=emlcntaolcom00000…)

15 years, 4 months

Facit 4431 terminal

by bqt＠softjar.se

Anyone have any docs for this terminal? It's a plain glass terminal. VT100-compatible. I have a problem with mine, and don't have any kind of documentation. I do see that the data lines have junk on them, and the serial port isn't working. But internal tests pass, and the setup and local mode works fine. Johnny -- Johnny Billquist || "I'm on a bus || on a psychedelic trip email: bqt at softjar.se || Reading murder books pdp is alive! || tryin' to stay hip" - B. Idol

15 years, 4 months

Correction to earlier posting about 5 + q inch diskettes

by gagnonr＠vif.com

I have approximately 1 1/2 banker's boxes (crates) full of 5 1/4" DSDD diskettes in their boxes. I am located in Montreal, Canada. Thanks, Robin Gagnon, Ph.D. Psychology Department Dawson College

15 years, 4 months

5 + q inch diskettes, crate full

by gagnonr＠vif.com

I have a banker's box full of 5 1/4" diskettes, in their original boxes, DSDD, of various brands. I haven't counted, but probably a few hundred. A few packages unopened. These diskettes were largely used to run back-ups, so didn't get much wear and tear. Would prefer that some classic computer collector rescue these rather than have them end up in landfill. The whole crate is yours for 20$ gagnonr (at sign) vif.com Robin Gagnon, Ph.D. Psychology Department Dawson College

15 years, 4 months

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test-drb December 2008