Re: Looking for Limited Function Board
Hi Paul I have put pictures of the boards here: http://pdp8.se/slask/LFB have.jpg is the board I have and want.jpg is the one I'm looking for. The identifying numbers are in aproximately the same place. But you can clearly see that the "want" board is much simplified and if I interpret the documentation correctly they are not compatible. I'm happy to be proven wrong, maybe I should just try it. /P On Tue, Feb 05, 2019 at 07:54:39PM -0600, Paul Anderson via cctalk wrote: > Hi Pontus, > > I looked at my limited function front panels, and they were 54-11507s. I > have not looked at any prints. Where did you find the 54-11165 number? > Could it be for a Q-bus system? > > The 50-X is the etched PCB. DEC usually added a 1 to that number to > make it complete board. > > Thanks, Paul > > > > On Mon, Feb 4, 2019 at 9:41 PM Paul Anderson wrote: > > > I have a few of the limited function and programmers panels. I do not > > recall either of them being dependent on particular backplane. I'll try to > > pull a few a few later and check the part number on them. > > > > Remember, a 54-X number can become a 70-X with the addition of a > > cable or something simple. > > > > Paul > > > > On Mon, Feb 4, 2019 at 12:51 PM Anders Sandahl via cctech < > > cct...@classiccmp.org> wrote: > > > >> > Date: Sun, 3 Feb 2019 22:22:42 +0100 > >> > From: Pontus Pihlgren > >> > To: "General Discussion: On-Topic and Off-Topic Posts" > >> > > >> > Subject: Looking for Limited Function Board > >> > Message-ID: <20190203212242.gf24...@update.uu.se> > >> > Content-Type: text/plain; charset=us-ascii > >> > > >> > Hi > >> > > >> > I'm restoring a PDP-8/a with the help of some > >> > friends. The CPU is now passing the MAINDECs I've > >> > thrown at it. The memory is a modern semiconductor > >> > board my friend Anders Sandahl made. > >> > > >> > This machine is pieced together from several others > >> > and the limited function panel I got does not match > >> > the backplane I have. > >> > > >> > My theory is the DEC simplified the design of the > >> > boardto cut costs and simpler design is not > >> > compatible. Mine is labeled (on the PCB): > >> > > >> > "LIMITED FUNCTION BD. > >> > 5411507 > >> > 5011506C-P2" > >> > > >> > And the one I need is: > >> > > >> > "LIMITED FUNCTION > >> > 5411165 > >> > 5011167" > >> > > >> > However, the picture I have of the other is not so > >> > good. I may have read the numbera wrong. > >> > > >> > I would very much like to buy one to finish this > >> > project. > >> > > >> > /P > >> > >> Får du inget napp så ritar jag upp ett kort till dig, det borde gå att > >> flytta över brytarna från det du har. Lite synd att scrappa ett > >> originalkort bara, men är man försiktigt så man inte tar sönder det så går > >> det ju att återställa... > >> > >> /A > >> > >>
Re: Looking for Limited Function Board
Hi, I have looked into my PDP-8/a computers now. The small one have the limited function board that you want. That is the machine that should be identical to yours. In my big PDP-8a/420 I have the same board as you have "have.jpg" but in another revision (no IDC header connector, just the DIL connector). The big machine is a core memory machine. I had a quick look at the schematics, they are not compatible. /Anders > Hi Paul > > I have put pictures of the boards here: > > http://pdp8.se/slask/LFB > > have.jpg is the board I have and want.jpg is the one > I'm looking for. > > The identifying numbers are in aproximately the same > place. But you can clearly see that the "want" board > is much simplified and if I interpret the > documentation correctly they are not compatible. > > I'm happy to be proven wrong, maybe I should just try > it. > > /P > > > On Tue, Feb 05, 2019 at 07:54:39PM -0600, Paul Anderson via cctalk wrote: >> Hi Pontus, >> >> I looked at my limited function front panels, and they were 54-11507s. I >> have not looked at any prints. Where did you find the 54-11165 number? >> Could it be for a Q-bus system? >> >> The 50-X is the etched PCB. DEC usually added a 1 to that number to >> make it complete board. >> >> Thanks, Paul >> >> >> >> On Mon, Feb 4, 2019 at 9:41 PM Paul Anderson wrote: >> >> > I have a few of the limited function and programmers panels. I do not >> > recall either of them being dependent on particular backplane. I'll >> try to >> > pull a few a few later and check the part number on them. >> > >> > Remember, a 54-X number can become a 70-X with the addition of >> a >> > cable or something simple. >> > >> > Paul >> > >> > On Mon, Feb 4, 2019 at 12:51 PM Anders Sandahl via cctech < >> > cct...@classiccmp.org> wrote: >> > >> >> > Date: Sun, 3 Feb 2019 22:22:42 +0100 >> >> > From: Pontus Pihlgren >> >> > To: "General Discussion: On-Topic and Off-Topic Posts" >> >> > >> >> > Subject: Looking for Limited Function Board >> >> > Message-ID: <20190203212242.gf24...@update.uu.se> >> >> > Content-Type: text/plain; charset=us-ascii >> >> > >> >> > Hi >> >> > >> >> > I'm restoring a PDP-8/a with the help of some >> >> > friends. The CPU is now passing the MAINDECs I've >> >> > thrown at it. The memory is a modern semiconductor >> >> > board my friend Anders Sandahl made. >> >> > >> >> > This machine is pieced together from several others >> >> > and the limited function panel I got does not match >> >> > the backplane I have. >> >> > >> >> > My theory is the DEC simplified the design of the >> >> > boardto cut costs and simpler design is not >> >> > compatible. Mine is labeled (on the PCB): >> >> > >> >> > "LIMITED FUNCTION BD. >> >> > 5411507 >> >> > 5011506C-P2" >> >> > >> >> > And the one I need is: >> >> > >> >> > "LIMITED FUNCTION >> >> > 5411165 >> >> > 5011167" >> >> > >> >> > However, the picture I have of the other is not so >> >> > good. I may have read the numbera wrong. >> >> > >> >> > I would very much like to buy one to finish this >> >> > project. >> >> > >> >> > /P >> >> >> >> Får du inget napp så ritar jag upp ett kort till dig, det borde gå >> att >> >> flytta över brytarna från det du har. Lite synd att scrappa ett >> >> originalkort bara, men är man försiktigt så man inte tar sönder det >> så går >> >> det ju att återställa... >> >> >> >> /A >> >> >> >> >
Looking for: 68000 C compilers
Hi, I'm (still) trying to reverse-engineer a ton of M68K ROM code which was apparently compiled with a circa-1990 C compiler. Does anyone have copies of any of the following -- or any other C compilers for the 68K which were around at that time? * Sierra Systems 68000 C compiler (was part of some Sega Genesis developer kits) * HP 68000 C compiler (either the HP 64000 or MSDOS versions) (I believe this was sold as the "HP B3640 Motorola 68000 Family C Cross Compiler) * Lattice C * Anything not on this list ;) My game plan is to take the compiled standard libraries from these compilers and build up some patterns/"fingerprints" to try and make a better guess at what the code is up to. I figure if I can at least pin down the stdlib and floating-point code, I have a better chance at figuring out what the main code does. I've seen the HP cross compiler manual on Bitsavers, but the compiler itself doesn't seem to be on bitsavers/bits. Thanks. -- Phil. phil...@philpem.me.uk http://www.philpem.me.uk/
Re: Looking for: 68000 C compilers
On 2019-02-06 10:08, Phil Pemberton via cctalk wrote: > Hi, > > I'm (still) trying to reverse-engineer a ton of M68K ROM code which was > apparently compiled with a circa-1990 C compiler. > AT&T B1 UNIX? And, we did at this time a lot on the OS/9 on microware. But I shink there is still a copyright on it ... Cheers
Re: Looking for: 68000 C compilers
On Wed, Feb 06, 2019 at 03:08:14PM +, Phil Pemberton via cctalk wrote: > Hi, > > I'm (still) trying to reverse-engineer a ton of M68K ROM code which > was apparently compiled with a circa-1990 C compiler. > > Does anyone have copies of any of the following -- or any other C > compilers for the 68K which were around at that time? [...] > > * Lattice C > > * Anything not on this list ;) Aztec C, by Manx Software (by now probably defunct). The Official Aztec C Online Museum: http://www.aztecmuseum.ca/index.htm stuff (those guys did a lot of them): http://www.aztecmuseum.ca/compilers.htm -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Looking for: 68000 C compilers
On Wed, Feb 6, 2019 at 9:08 AM Phil Pemberton via cctalk wrote: > I'm (still) trying to reverse-engineer a ton of M68K ROM code which was > apparently compiled with a circa-1990 C compiler. I used to do a lot of m68k ROM code development c. 1985-1993... > Does anyone have copies of any of the following -- or any other C > compilers for the 68K which were around at that time? >* Lattice C Yes. For AmigaDOS... >* Anything not on this list ;) We rolled our own m68k cross assembler that ran on VMS, twice - one was a very simple, unsophisticated assembler that just took blocks of code and banged out a monolithic OBJ, and later, a fancier one with relocatable blocks and multiple sections that produced more of a "loader format" for linking multiple entities together.I have the source for these but they are definitely K&R C and may have some file routines that would have to be lightly massaged out of VMS-isms. -ethan
RE: Another dealer going under
> Calabasas, CA Well for a change it is someone just next door so I can definitely take a look. I wonder if they have anything available. Do you have contact info/address? -Ali > > -Original Message- > From: Ali [mailto:cct...@ibm51xx.net] > Sent: Tuesday, February 05, 2019 2:57 PM > To: 'Electronics Plus'; 'General Discussion: On-Topic and Off-Topic > Posts' > Subject: RE: Another dealer going under > > > > I don't get replies from here yet, so I have seen no replies to my > > posts, > > nor the posts themselves. > > > > There is a shop that has been in biz for over 25 years that is > closing > > in > > California. > > > > Cindy, > > Where in CA? It's a big state :) > > -Ali
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
At 06:53 PM 2/5/2019, you wrote: Some years ago, Jay recommended a Genie Load Lifter to me (thank you!), and I was fortunate enough to get two of them as "new old stock" for about half price. They're relatively inexpensive and absolutely invaluable. Put a 200lb unit into the top of a full height rack? No problem. Shame I had to leave both behind when I left that employment (especially since they bought a third one but never used it)! Pete Pete Turnbull Pete - That Genie Load Lifter gizmo looks great - and I wish I had one on Sunday when I was horsing those HP drives around. They are not cheap - a used one on eBay for $600. But, what is a back worth? Best, Jack in the Rocky Mountains. -- Jack Harper, President Secure Outcomes Inc 2942 Evergreen Parkway, Suite 300 Evergreen, Colorado 80439 USA 303.670.8375 303.670.3750 (fax) http://www.secureoutcomes.net for Product Info.
RE: Another dealer going under
A Plus Computer Products 5115 N. Douglas Fir Road Suite N Calabasas, CA 91302 Leslie Foumberg, Owner Leslie Foumberg [les...@apluscp.com] You might try emailing her directly. I have sent her an email letting her know she might start getting some oddball requests. Also requested a spreadsheet of inventory, or lots of pics on a shared link, and then you can email her your interest. Sorry, but I have a sick husband right now, and no time to play intermediary. Cindy --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
At 01:59 PM 2/5/2019, you wrote: by my lonesome, I was determined not to repeat the process. The rack, VTW, is from an old HP Storage Array, which has a nice anti-tip pullout on the bottom. I constructed a dolly for the HP drive that allows me to roll it around where I need it. It's low enough that it can slip under a table. I should have done the same for the Fuji drive, now that i think about it. I leave the heavy lifting to the young bucks like yourself. When you break one of the retention levers (they get brittle with age), drop me a line. I have some 3D printed up from nylon that work just fine. --Chuck Thank You Chuck - You are correct - I would never try that again. I appreciate the offer on the retension levers on the HP 7970. Best, Jack in the Rocky Mountains (cold and snowy day here at a forecast -2F :) -- Jack Harper, President Secure Outcomes Inc 2942 Evergreen Parkway, Suite 300 Evergreen, Colorado 80439 USA 303.670.8375 303.670.3750 (fax) http://www.secureoutcomes.net for Product Info.
RE: Looking for: 68000 C compilers
Phil I doubt if its relevant but I think I have Sozobon C for the Atari. There was also a Mark Williams "C" https://en.wikipedia.org/wiki/Mark_Williams_Company http://www.atari-forum.com/viewtopic.php?t=25148 and of course various GNU ports. Dave > -Original Message- > From: cctalk On Behalf Of Phil Pemberton > via cctalk > Sent: 06 February 2019 15:08 > To: cctalk@classiccmp.org > Subject: Looking for: 68000 C compilers > > Hi, > > I'm (still) trying to reverse-engineer a ton of M68K ROM code which was > apparently compiled with a circa-1990 C compiler. > > Does anyone have copies of any of the following -- or any other C compilers > for the 68K which were around at that time? > >* Sierra Systems 68000 C compiler (was part of some Sega Genesis > developer kits) > >* HP 68000 C compiler (either the HP 64000 or MSDOS versions) > (I believe this was sold as the "HP B3640 Motorola 68000 Family C > Cross Compiler) > >* Lattice C > >* Anything not on this list ;) > > My game plan is to take the compiled standard libraries from these compilers > and build up some patterns/"fingerprints" to try and make a better guess at > what the code is up to. > I figure if I can at least pin down the stdlib and floating-point code, I have a > better chance at figuring out what the main code does. > > I've seen the HP cross compiler manual on Bitsavers, but the compiler itself > doesn't seem to be on bitsavers/bits. > > Thanks. > -- > Phil. > phil...@philpem.me.uk > http://www.philpem.me.uk/
360Tech is gone
Last May Steve auctioned off the assets, and and printer/plotter co bought the name and website. Steve retired to Hawaii. All is gone L Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 830-370-3239 cell sa...@elecplus.com --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
RE: Mounting HP7970e 9-Trk 1/2" Tape Drive
Chuck's retension levers any chance this is on thingiverse or would you be willing to send me the .stl file so I can 3dprint my own? :) I have not looked at my 7970's in quite some time, but I had thought the previous discussion was for mounting the 7970's in an HP rack. Not all later HP racks, but the 2 or 3 series that were predominant around the time of the 7970's, had a very specific build related to positioning of the holes (which were actually a few sliding metal bars with tapped holes, not just holes all up and down the rack). The 7970 mounting bracket was designed for that 'odd' HP-way the racks were built at that time (they changed later). I do not think that an HP rack called a "storage array" (obviously much later production) would have the same hole (and more importantly, the channels around the bars) pattern. Long story short, I am not positive that mounting the 7970 in a non-HP or HP but non-period rack would work 100% as originally intended. It may stay in the rack, but there could be some positional/operational issues. Specifically what I'm wondering, without the bracket and in a "non-hp" hp rack ;)... how did you bolt it on the left hand side? And are you sure that with it mounted that way, the speed bolt on the front right inside the door allows you to swing the unit all the way open without hitting the flush surface on the left of the casting? I need to go look at mine and see if I'm just remembering this all wrong... lol J
Re: Looking for: 68000 C compilers
On Wed, Feb 6, 2019 at 10:27 AM Ethan Dicks wrote: > On Wed, Feb 6, 2019 at 9:08 AM Phil Pemberton via cctalk > wrote: > > I'm (still) trying to reverse-engineer a ton of M68K ROM code which was > > apparently compiled with a circa-1990 C compiler. > > > Does anyone have copies of any of the following -- or any other C > > compilers for the 68K which were around at that time? > >* Anything not on this list ;) > > We rolled our own m68k cross assembler... I'm also remembering that the cost of a C compiler that ran on VMS but emitted m68k code was insanely expensive in the late 1980s (many thousands of dollars) so for one project, we purchased a Perkin Elmer 7350 workstation and it was both the software development environment for the team _and_ we used its C compiler to generate m68k assembler, which we then fed to our home-grown cross-assembler because we needed our binary format, not a.out. It really was the cheapest way to do that 30 years ago. OTOH, at home, I'd had an Amiga since 1986 and used a variety of native tools (Lattice C later SAS/C, and various assemblers either commercial or from a Fish Disk). -ethan
old barcode and scanner equip
Preowned Barcode Ltd John Gallant Halifax NS Canada PH (902) 468 8210 Cell (902)719 6031 Email: sa...@preownedbarcode.com This gent has stuff from the 80s and 90s in the barcode and scanner departments. Not affiliated with seller, etc. Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 830-370-3239 cell sa...@elecplus.com --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2/6/19 10:09 AM, Jay West wrote: > I have not looked at my 7970's in quite some time, but I had thought the > previous discussion was for mounting the 7970's in an HP rack. Not all later > HP racks, but the 2 or 3 series that were predominant around the time of the > 7970's, had a very specific build related to positioning of the holes (which > were actually a few sliding metal bars with tapped holes, not just holes all > up and down the rack). The 7970 mounting bracket was designed for that 'odd' > HP-way the racks were built at that time (they changed later). I do not > think that an HP rack called a "storage array" (obviously much later > production) would have the same hole (and more importantly, the channels > around the bars) pattern. Long story short, I am not positive that mounting > the 7970 in a non-HP or HP but non-period rack would work 100% as > originally intended. It may stay in the rack, but there could be some > positional/operational issues. The HP disk array rack is a pretty standard 19" EIA rack, with some extra slots for mounting the disk drive slides. Looking at the 7970, without the mounting kit, it's a standard 19" wide. The right side flange has holes for mounting; the left side (the side with the support hinges for the works) has a similar flange, but without holes. Since mounting holes on an 19" rack are 18" apart, I could see where just boring a couple of holes in the hinge-side flange and countersinking them for flathead bolts would work to secure the drive. On the DA cabinet, however, the side "skins" project about an inch forward of the mounting rails, so you'd probably have to remove one to get clearance to open the drive up for servicing. On the other hand, a "naked" rack would probably work just fine. My Fujitsu drive was new when I got it and so came with its own mounting slides. Still is a heavy bugger, though. --Chuck
Re: PDP-11/45 RSTS/E boot problem
> From: Mattis Lind >> we've also looked at what's in memory at that location, and the low >> part of the text segment seems to be correct, but there was junk at >> the top, around the target of the JSR (i.e. at 'csv'). Not just one >> word, but everything around that location was wrong, which would >> suggest to me that the cause is not a simple memory failure there. >> I've suggested to Fritz that we look at that again, to see if what was >> recorded before is accurate > Would it be possible to insert a breakpoint or halt and run the > program, insert original instruction and single step? I'm not sure that's going to tell us much: the latest development is that Fritz looked at the actual memory contents again, and it is once again trash; _almost_ identical to what was there before: PA:171600: 016162 004767 000224 000414 006700 006152 006702 006144 but with some extra 01 bits: PA:171600: 016162 004767 000224 000414 016700 016152 016702 016144 (It's not clear if this represents a real difference, or if that front panel issue Fritz mentioned caused the contents to be displayed incorrectly.) The exciting thing is that if the latter really is what's in main memory, that '16700 16152' at the PC of the MM trap could indeed generate the MM trap we're seeing: it's "MOV 26364, R0", and that address is in segment (page) 1, which is only 03500 long If so, i) we're down to one problem (good news), and our problem turns into finding out how that section of the code got trashed (bad news). Which is not going to be simple, alas, I suspect. I don't think it's the RK11, because Unix reads the program image into system buffers in low memory, and that's clearly working OK in the 'sleep;ls' case. (It may not use the exact same buffers, though...) It then copies it out to the memory where it's going to execute from, using an MTPI loop. So maybe the memory still has issues, or maybe the MTPI isn't working with some main memory locations or or or... Noel
RE: Mounting HP7970e 9-Trk 1/2" Tape Drive
Chuck wrote... -- The HP disk array rack is a pretty standard 19" EIA rack, with some extra slots for mounting the disk drive slides. Looking at the 7970, without the mounting kit, it's a standard 19" wide. The right side flange has holes for mounting; the left side (the side with the support hinges for the works) has a similar flange, but without holes. Since mounting holes on an 19" rack are 18" apart, I could see where just boring a couple of holes in the hinge-side flange and countersinking them for flathead bolts would work to secure the drive. On the DA cabinet, however, the side "skins" project about an inch forward of the mounting rails, so you'd probably have to remove one to get clearance to open the drive up for servicing. On the other hand, a "naked" rack would probably work just fine. - Yes, it's all "standard 19 inch" but. the HP gear and mounting kits of that time expected certain things to be present in the rack design/construction well beyond just the space between the vertical posts. As I recall, on the left, the flange (where mounting holes are - on the right) does not have mounting holes. And drilling and tapping would be difficult because a 2 inch thick piece of solid metal from the side of the casting covers those. You would only be able to screw them in from the back, and in many racks that wouldn't be possible. Not to mention that part of that solid metal casting cantilevers when the unit is in the service position, so drilling all the way through (or anchoring the casting) is going to disallow getting to stuff you want to get to. And if you can't use the internal access door as-mounted, I'd bet the chance of injury or damage goes up exponentially every time you need to pull it out of the rack so you can get to stuff. There ARE bolt holes for attaching on the left, but they are not on the flange as they are on the right side. They are on the left side of the aluminum housing, about 7 inches back from the front, in a vertical line. You're not going to find a rack that has attach points there, and those are the PRIMARY attach points for the entire left hand side (and they are in aluminum housing, so absolutely depend on the steel bracket on the left for weight support). I'm wondering if connecting the tape unit by using bolts along the outer flanges (assuming they were present on left and right - which they weren't) may not be sufficient given the weight of the unit. That is why the special HP mounting bracket has an L-angle on the bottom, to take much of the weight of the unit. Without it (ie. in a non-(hp-period)standard rack) I wonder if the flanges really aren't designed to hold that kind of weight. So... I'm curious how they were actually mounted on the left in that particular rack. The only method I've ever seen that mostly works is using L-brackets under the unit. But that still doesn't attach the left side. Some may be ok with that I'm sure. I myself have visions of 150# of mostly cast aluminum and steel coming off those L brackets and they would bend the right racksupport severely (or the tape unit) for sure. I'm not at all saying it can't be done and done sufficiently. I'm just curious how :) I've been blessed with the right brackets and racks, so never had to mess with it. And like I said, haven't laid eyes on my 7970s in over a year, so my memory is prolly foggy :) J
Re: Looking for: 68000 C compilers
> From: Phil Pemberton > * Anything not on this list ;) The TRIX project at MIT-LCS did a 68K compiler very early on (soon after the first 68K wa released)x, using Steve Johnson's Portable C Compiler as a base. Noel
Re: Looking for: 68000 C compilers
At 12:26 PM 2/6/2019, Ethan Dicks via cctalk wrote: >OTOH, at home, I'd had an Amiga since 1986 and used a variety of >native tools (Lattice C later SAS/C, and various assemblers either >commercial or from a Fish Disk). Somewhere I have the DOS-hosted C compiler for the Amiga that was part of the first developer kits. I think they were Sage-hosted for a while, too. - John
NIB 1986 phones and used USR modems
Pics of equipment on request.
Hi, we occasionally get some.
For example, we have the following:
2x Phones ROLM 61000 in boxes (see photos) ('86 year of manufacture); Bunch
of (see photos):
FAX-MODEM USRobotics 33.6K Model 0459 PN: 00083907
FAX-MODEM USRobotics 56K Model 0701PN: USR5686D
FAX-MODEM USRobotics 56K V.92 PN: 5686
Let me know what you think.
I'll keep you posted on any antique equipment we will be receiving.
Nick Makarovskiy,
n...@ictcompany.com
Office: +1-781-912-1717 x 710
Direct:+1-781-912-1710
Cell/WhatsApp: +1-617-309-8705
400 Tradecenter, Ste 5900
Woburn MA 01801
Not affiliated with seller, etc.
Cindy Croxton
Electronics Plus
1613 Water Street
Kerrville, TX 78028
830-370-3239 cell
sa...@elecplus.com
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
Unused Sun keyboard and accessories
1 keyboard PN 3201072-01 still in plastic and foam (Type 5) 1 metallic type mousepad, never used 1 mouse 370-1170-01, used 1 cable 530-1594-01 used 1 cable 530-1662-01 new 1 cable 530-1442-02 used 1 battery holder that is plugged into the 530-1594-01, used, no battery installed These are in my stock. All fits in one box. Make offer. Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 830-370-3239 cell sa...@elecplus.com --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2/6/19 11:25 AM, Jay West wrote: > Yes, it's all "standard 19 inch" but. the HP gear and mounting > kits of that time expected certain things to be present in the rack > design/construction well beyond just the space between the vertical > posts. > > As I recall, on the left, the flange (where mounting holes are - on > the right) does not have mounting holes. And drilling and tapping > would be difficult because a 2 inch thick piece of solid metal from > the side of the casting covers those... Okay, here's what I'm talking about. Take a look at PDF page 6 from this document: http://bitsavers.informatik.uni-stuttgart.de/pdf/hp/tape/7970/07970-90383_7970B_7970C_Operating_and_Service_Manual_upd_Feb76/07970-90383_7970B_7970C_Operating_and_Service_Manual_Section_1.pdf This shows very clearly the naked "box" without the transport works. Said box is aluminum, with 1/8" or so thick flanges on each side. Note that the right side has 3 mounting slots (and the transport has 3 "notches" to make room for bolt heads and washers. Now look at the right side of the drive box. Note that the hinges for the transport are secured to a similar flange, but without any mounting holes. I propose that drilling a couple of mounting holes to match rack spacing and countersinking said holes so that they don't interfere with the transport body would do the trick. My rack uses cage nuts on the rails, so there would be no fiddling with nuts and bolts. I'd probably also feel better if the rear of the drive were secured to the rack also, but I haven't worked that one out yet--nor am I likely too, as my current setup works just fine without the danger of hernia. --Chuck
Re: Looking for: 68000 C compilers
I know there's an old (I think) official Sega Genesis devkit that's, erm, "around" on various console homebrew sites. No idea which exact C compiler is included, but it's not too difficult to find.
Re: PDP-11/45 RSTS/E boot problem
On 2019-Feb-06, at 10:53 AM, Noel Chiappa via cctalk wrote: > > I'm not sure that's going to tell us much: the latest development is that > Fritz looked at the actual memory contents again, and it is once again > trash; _almost_ identical to what was there before: > > PA:171600: 016162 004767 000224 000414 006700 006152 006702 006144 > > but with some extra 01 bits: > > PA:171600: 016162 004767 000224 000414 016700 016152 016702 016144 > > (It's not clear if this represents a real difference, or if that > front panel issue Fritz mentioned caused the contents to be displayed > incorrectly.) > > The exciting thing is that if the latter really is what's in main memory, > that '16700 16152' at the PC of the MM trap could indeed generate the MM trap > we're seeing: it's "MOV 26364, R0", and that address is in segment (page) 1, > which is only 03500 long > > If so, i) we're down to one problem (good news), and our problem turns into > finding out how that section of the code got trashed (bad news). Which is not > going to be simple, alas, I suspect. I don't think it's the RK11, because > Unix reads the program image into system buffers in low memory, and that's > clearly working OK in the 'sleep;ls' case. (It may not use the exact same > buffers, though...) It then copies it out to the memory where it's going to > execute from, using an MTPI loop. So maybe the memory still has issues, or > maybe the MTPI isn't working with some main memory locations or or or... I haven't followed this in detail enough to know what the configuration and memory board at play are so maybe this can be ruled out from your end, but for consideration, what about the refresh circuitry of the memory board? Mem diagnostics, unless they explicitly account for it, may not show up problems with memory refresh if the loop times are short enough to effectively substitute as refresh cycles, while they could show up later in real-world use with arbitrary time between accesses. Refresh on some early boards/systems was asynchronously timed by monostables or onboard oscillators which can drift or fail on the margin/slope. (I don't know what DEC's design policy was for DRAM refresh). It might also explain why a number of 4116s were (apparently) failing earlier in the efforts (if I recall the discussion correctly), replacing them might have just replaced them with 'slightly better' chips, i.e. with a slightly longer refresh tolerance.
Re: another dealer going under
Leslie is preparing a list. She has also contacted another friend who is quitting the biz, to see if they want to get rid of equip. Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 830-370-3239 cell sa...@elecplus.com --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Re: Looking for: 68000 C compilers
Hi, I could offer Lattice C 3 and 5 for 68k / Atari ST. Regards Götz ... auf dem Sprung ... > Am 06.02.2019 um 17:21 schrieb Tomasz Rola via cctalk : > >> On Wed, Feb 06, 2019 at 03:08:14PM +, Phil Pemberton via cctalk wrote: >> Hi, >> >> I'm (still) trying to reverse-engineer a ton of M68K ROM code which >> was apparently compiled with a circa-1990 C compiler. >> >> Does anyone have copies of any of the following -- or any other C >> compilers for the 68K which were around at that time? > [...] >> >> * Lattice C >> >> * Anything not on this list ;) > > Aztec C, by Manx Software (by now probably defunct). > > The Official Aztec C Online Museum: > > http://www.aztecmuseum.ca/index.htm > > stuff (those guys did a lot of them): > > http://www.aztecmuseum.ca/compilers.htm > > -- > Regards, > Tomasz Rola > > -- > ** A C programmer asked whether computer had Buddha's nature. ** > ** As the answer, master did "rm -rif" on the programmer's home** > ** directory. And then the C programmer became enlightened... ** > ** ** > ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Looking for: 68000 C compilers
On Wed, Feb 06, 2019 at 06:44:27PM +0100, Götz Hoffart wrote: > Hi, > > I could offer Lattice C 3 and 5 for 68k / Atari ST. > > Regards > Götz Lattice was the thing, back when I had Amiga. Too bad I could not afford a harddisk :-). BTW, I just recalled the Aminet is still there and seems to be quite active, although I guess activity nowadays mostly revolves around PPC-based models with Workbench 4(++).x(++), but they have /dev section and quite a few compilers in there: http://aminet.net/tree?path=dev After all, who said it was a C compiler? Most probably, it was C compiler, yes. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Looking for: 68000 C compilers
I have a copy of the source for a set of 68k tools (compiler, assembler, loader, etc) which was based on work done by Chris Terman at MIT. This work was done back in the mid 80s, so some work is likely needed to compile with modern tools. Let me know if you would like a copy. On 2/6/19 10:27 AM, Ethan Dicks via cctalk wrote: > On Wed, Feb 6, 2019 at 9:08 AM Phil Pemberton via cctalk > wrote: >> I'm (still) trying to reverse-engineer a ton of M68K ROM code which was >> apparently compiled with a circa-1990 C compiler. > I used to do a lot of m68k ROM code development c. 1985-1993... > >> Does anyone have copies of any of the following -- or any other C >> compilers for the 68K which were around at that time? >>* Lattice C > Yes. For AmigaDOS... > >>* Anything not on this list ;) > We rolled our own m68k cross assembler that ran on VMS, twice - one > was a very simple, unsophisticated assembler that just took blocks of > code and banged out a monolithic OBJ, and later, a fancier one with > relocatable blocks and multiple sections that produced more of a > "loader format" for linking multiple entities together.I have the > source for these but they are definitely K&R C and may have some file > routines that would have to be lightly massaged out of VMS-isms. > > -ethan >
Re: PDP-11/45 RSTS/E boot problem
> From: Brent Hilpert > what about the refresh circuitry of the memory board? > ... > It might also explain why a number of 4116s were (apparently) failing > earlier in the efforts ... replacing them might have just replaced them > with 'slightly better' chips, i.e. with a slightly longer refresh tolerance. Ooh, excellent idea! Noel
Re: Looking for: 68000 C compilers
On Wed, Feb 06, 2019 at 10:13:57PM +0100, Tomasz Rola via cctalk wrote: [...] > quite a few compilers in there: > > http://aminet.net/tree?path=dev And on page 1 of 5 in /dev/asm section I have spotted at least two disassemblers, there might be more. Caution: never used any. http://aminet.net/dev/asm ADisV1_3.lha - 'Intelligent' Disassembler (incl.source) Bin2Asm.lha - Binary to assembler source converter etc. -- Regards, Tomasz Rola -- ** A C programmer asked whether computer had Buddha's nature. ** ** As the answer, master did "rm -rif" on the programmer's home** ** directory. And then the C programmer became enlightened... ** ** ** ** Tomasz Rola mailto:tomasz_r...@bigfoot.com **
Re: Looking for: 68000 C compilers
On 2/6/19 1:23 PM, Tomasz Rola via cctalk wrote: > On Wed, Feb 06, 2019 at 10:13:57PM +0100, Tomasz Rola via cctalk > wrote: [...] >> quite a few compilers in there: >> >> http://aminet.net/tree?path=dev > > And on page 1 of 5 in /dev/asm section I have spotted at least two > disassemblers, there might be more. Caution: never used any. > > http://aminet.net/dev/asm > > ADisV1_3.lha - 'Intelligent' Disassembler (incl.source) Bin2Asm.lha - > Binary to assembler source converter I used Mark WIlliams C on the Atari ST. --Chuck
Re: Unused Sun keybaord and accessories
This keyboard has now been sold! Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 830-370-3239 cell sa...@elecplus.com --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
Re: Another dealer going under
I an next door, give us the address please... Thanks, Randy From: cctalk on behalf of Ali via cctalk Sent: Wednesday, February 6, 2019 9:07 AM To: 'General Discussion: On-Topic and Off-Topic Posts' Cc: 'Electronics Plus' Subject: RE: Another dealer going under > Calabasas, CA Well for a change it is someone just next door so I can definitely take a look. I wonder if they have anything available. Do you have contact info/address? -Ali > > -Original Message- > From: Ali [mailto:cct...@ibm51xx.net] > Sent: Tuesday, February 05, 2019 2:57 PM > To: 'Electronics Plus'; 'General Discussion: On-Topic and Off-Topic > Posts' > Subject: RE: Another dealer going under > > > > I don't get replies from here yet, so I have seen no replies to my > > posts, > > nor the posts themselves. > > > > There is a shop that has been in biz for over 25 years that is > closing > > in > > California. > > > > Cindy, > > Where in CA? It's a big state :) > > -Ali
Re: PDP-11/45 RSTS/E boot problem
On 2019-Feb-06, at 1:21 PM, Noel Chiappa via cctalk wrote: >> From: Brent Hilpert > >> what about the refresh circuitry of the memory board? >> ... >> It might also explain why a number of 4116s were (apparently) failing >> earlier in the efforts ... replacing them might have just replaced them >> with 'slightly better' chips, i.e. with a slightly longer refresh tolerance. > > Ooh, excellent idea! Is the schematic available for the memory board at-issue? Curious myself to see what approach for refresh DEC used.
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2019-Feb-06, at 12:24 PM, Chuck Guzis via cctalk wrote: > On 2/6/19 11:25 AM, Jay West wrote: > >> Yes, it's all "standard 19 inch" but. the HP gear and mounting >> kits of that time expected certain things to be present in the rack >> design/construction well beyond just the space between the vertical >> posts. >> >> As I recall, on the left, the flange (where mounting holes are - on >> the right) does not have mounting holes. And drilling and tapping >> would be difficult because a 2 inch thick piece of solid metal from >> the side of the casting covers those... > > Okay, here's what I'm talking about. Take a look at PDF page 6 from > this document: > > http://bitsavers.informatik.uni-stuttgart.de/pdf/hp/tape/7970/07970-90383_7970B_7970C_Operating_and_Service_Manual_upd_Feb76/07970-90383_7970B_7970C_Operating_and_Service_Manual_Section_1.pdf > > This shows very clearly the naked "box" without the transport works. > Said box is aluminum, with 1/8" or so thick flanges on each side. > > Note that the right side has 3 mounting slots (and the transport has 3 > "notches" to make room for bolt heads and washers. > > Now look at the right side of the drive box. (I take it you mean "now look at the -left- side".) If you drill holes in the left-side flange for rack mounting, you have to be able to access them at mount time, which is not possible with the drive fully assembled. However, looking at my 7970A, it appears you could separate the cast-Al transport frame from the chassis box by unscrewing the 4 exterior left-side hinge screws, as well as detaching all the cabling between them involving a wire harness and a dozen-or-so plugs. This would have the benefit of splitting up the weight involved in the mounting process. Holding the transport frame and aligning it with the hinges during reattachment while trying to get the screws in place might nonetheless require two people. In a slightly-alternate design, HP might have made the left-side bezel over the manual controls removable, giving access to the left-side flange without detaching the transport frame, but that would also require a slight modification to the casting near the screw holes for clearance for the screws. For loading concerns raised by Jay, in both cases (designed-for steel bracket vs drilled flange) the weight of the drive ends up being borne by 4 rack-screws on the left and 3 on the right. The difference would be steel vs Al bearing down on the 4 screws on the left, and some altered bending moments on the left side of the Al chassis box around the flange, offhand I wouldn't think it would matter. > Note that the hinges for > the transport are secured to a similar flange, but without any mounting > holes. I propose that drilling a couple of mounting holes to match > rack spacing and countersinking said holes so that they don't interfere > with the transport body would do the trick. My rack uses cage nuts on > the rails, so there would be no fiddling with nuts and bolts. I'd > probably also feel better if the rear of the drive were secured to the > rack also, but I haven't worked that one out yet--nor am I likely too, > as my current setup works just fine without the danger of hernia.
Re: PDP-11/45 RSTS/E boot problem
> On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk > wrote: > > Is the schematic available for the memory board at-issue? > Curious myself to see what approach for refresh DEC used. Yes, here: http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf There is also a technical manual adjacent, with circuit descriptions. I will scope this up tonight and take a look! --FritzM.
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
Jack Harper wrote: I got both drives into the rack this past weekend and I am an old guy (67) - I carefully stared at the thing before I started and finally figured out that I could, in fact, lift the drive from a waist high cart for a few seconds, but definitely could not lift it or lower it vertically with my arms - no way - and I would have one shot at getting the drives into the rack on the rails. Harbor Freight sells a nice hydraulic lift table for under $200 that I have found very useful for that sort of thing. It doesn't go up very high (like for the top of a rack), but I used it with some wood blocks to lift a DEC ES45 Alpha system into a rack by myself. 500 pound capacity, 28.5" lift height, $170 https://www.harborfreight.com/500-lbs-capacity-hydraulic-table-cart-61405.html 1000 pound capacity, 34.5" lift height, $260 https://www.harborfreight.com/1000-lbs-capacity-hydraulic-table-cart-69148.html Alan Frisbie
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2/6/19 2:29 PM, Brent Hilpert via cctalk wrote: > (I take it you mean "now look at the -left- side".) Well, you know, my *other* right... :) > However, looking at my 7970A, it appears you could separate the cast-Al > transport frame from the chassis box > by unscrewing the 4 exterior left-side hinge screws, as well as detaching all > the cabling between them involving > a wire harness and a dozen-or-so plugs. Swing the drive assembly out from the back cover--you'll note that the pivot points on the two hinges are about 1" away from the cover flange. You've got plenty of room to drill your mounting holes from the *rear* of that flange. You might even have enough clearance for a countersink--but that may not be necessary--the frame casting only extends in from the left about a half-inch--you may even clear some oval-headed screws or get away with some truss-head screws. Alternatively, could mill a slight relief in the casting to clear the heads. I think it's doable without removing the drive from the cover. > For loading concerns raised by Jay, in both cases (designed-for steel > bracket vs drilled flange) the weight of the drive ends up being > borne by 4 rack-screws on the left and 3 on the right. The difference > would be steel vs Al bearing down on the 4 screws on the left, and > some altered bending moments on the left side of the Al chassis box > around the flange, offhand I wouldn't think it would matter. I tend to agree--the force is mostly downward on the front of the drive. I suppose that you could reinforce the aluminum housing with some steel bar backing up the mounting flanges, but that seems like overkill to me. --Chuck
Re: PDP-11/45 RSTS/E boot problem
>> On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk >> wrote: >> >> Is the schematic available for the memory board at-issue? >> Curious myself to see what approach for refresh DEC used. > > Yes, here: > http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf For completeness, from the technical manual: "The refresh logic, shown in sheet 6 of the print set, generates REF CLK H and the refresh address. Sig- nal REF CLK H is derived from a 555 timer (E5) which is set up as a free running oscillator, powered by the + IS V / + 12 V module input (V-555). The REF CLK H signal oscillates with a period of 14.5us and has a positive pulse width of 6us during each period."
Re: PDP-11/45 RSTS/E boot problem
On 2019-Feb-06, at 5:11 PM, Fritz Mueller via cctalk wrote: >>> On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk >>> wrote: >>> >>> Is the schematic available for the memory board at-issue? >>> Curious myself to see what approach for refresh DEC used. >> >> Yes, here: >> http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf > > For completeness, from the technical manual: > > "The refresh logic, shown in sheet 6 of the print set, generates REF CLK H > and the refresh address. Sig- nal REF CLK H is derived from a 555 timer (E5) > which is set up as a free running oscillator, powered by the + IS V / + 12 V > module input (V-555). The REF CLK H signal oscillates with a period of 14.5us > and has a positive pulse width of 6us during each period." So I could have saved myself some fun if I had read the manual rather than just looking at the schematic. Not that they're way out of whack, but the mild disparity between the manual's 14.5uS and my calculated 11.7uS is curious (the calculation being based on the schematic RC values and the 555 equations).
Re: PDP-11/45 RSTS/E boot problem
> On Feb 6, 2019, at 8:25 PM, Brent Hilpert via cctalk > wrote: > > On 2019-Feb-06, at 5:11 PM, Fritz Mueller via cctalk wrote: On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk wrote: Is the schematic available for the memory board at-issue? Curious myself to see what approach for refresh DEC used. >>> >>> Yes, here: >>> http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf >> >> For completeness, from the technical manual: >> >> "The refresh logic, shown in sheet 6 of the print set, generates REF CLK H >> and the refresh address. Sig- nal REF CLK H is derived from a 555 timer (E5) >> which is set up as a free running oscillator, powered by the + IS V / + 12 V >> module input (V-555). The REF CLK H signal oscillates with a period of >> 14.5us and has a positive pulse width of 6us during each period." > > So I could have saved myself some fun if I had read the manual rather than > just looking at the schematic. > Not that they're way out of whack, but the mild disparity between the > manual's 14.5uS and my calculated 11.7uS is curious > (the calculation being based on the schematic RC values and the 555 > equations). Perhaps the period was changed in a schematic rev or ECO, and the manual wasn't updated to reflect it. It would be interesting to check the data sheet for the RAM chip to see what it likes for refresh cycle. And given that this is an RC oscillator your theory about out of tolerance timing definitely deserves checking. paul
Re: PDP-11/45 RSTS/E boot problem
On 2019-Feb-06, at 3:39 PM, Fritz Mueller wrote: >> On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk >> wrote: >> >> Is the schematic available for the memory board at-issue? >> Curious myself to see what approach for refresh DEC used. > > Yes, here: > http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf > > There is also a technical manual adjacent, with circuit descriptions. > > I will scope this up tonight and take a look! Mixed up To: fields. The following was intended to go to the list and was originally sent a moment before I saw Fritz's message mentioning the 555: Ha!, simple free-running 555 oscillator generating the refresh cycles (pdf.pg27). I suspect there is a mistake in the schematic there: V-555 more likely connects on the other side of R4 (E5.4-C1-R4, rather than E5.7-R4-R5) to make it into the standard 555 astable circuit. Based on that, calculations indicate that the output from E5 (TP18) should be around 85 KHz, cycling 6.4 uS high, 5.3 uS low. So it's generating a refresh cycle every 11.8 uS. With 7 bits used from counter E43 (128 rows) for full refresh, that's a cell refresh every 1.5mS which (without having checked the 4116 specs) sounds sensible for a DRAM from that period. Note the 555 (E5) is running on +12 or +15V, with a R voltage divider on the output before driving into TTL.
Re: PDP-11/45 RSTS/E boot problem
On 2019-Feb-06, at 5:29 PM, Paul Koning wrote: >> On Feb 6, 2019, at 8:25 PM, Brent Hilpert via cctalk >> wrote: >> On 2019-Feb-06, at 5:11 PM, Fritz Mueller via cctalk wrote: > On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk > wrote: > > Is the schematic available for the memory board at-issue? > Curious myself to see what approach for refresh DEC used. Yes, here: http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf >>> >>> For completeness, from the technical manual: >>> >>> "The refresh logic, shown in sheet 6 of the print set, generates REF CLK H >>> and the refresh address. Sig- nal REF CLK H is derived from a 555 timer >>> (E5) which is set up as a free running oscillator, powered by the + IS V / >>> + 12 V module input (V-555). The REF CLK H signal oscillates with a period >>> of 14.5us and has a positive pulse width of 6us during each period." >> >> So I could have saved myself some fun if I had read the manual rather than >> just looking at the schematic. >> Not that they're way out of whack, but the mild disparity between the >> manual's 14.5uS and my calculated 11.7uS is curious >> (the calculation being based on the schematic RC values and the 555 >> equations). > > Perhaps the period was changed in a schematic rev or ECO, and the manual > wasn't updated to reflect it. It would be interesting to check the data > sheet for the RAM chip to see what it likes for refresh cycle. And given > that this is an RC oscillator your theory about out of tolerance timing > definitely deserves checking. Checking further.. 4116 datasheet specs 2mS, my calcs give a refresh period of 1.5mS, the 14.5uS from the manual would give 1.86 mS, 7% shy of 2. The schematic specs 1% resistors, and the parts list does appear to spec a high-tolerance "1%200PPM" cap. Although there are the internal voltage divider Rs in the 555 which are also critical for the timing and everything is 40+ years old. Idle speculation at my distance, we'll see what Fritz observes. Could be other problems in the refresh circuitry too, like failed outputs from the row counter, etc.
Re: PDP-11/45 RSTS/E boot problem
On 02/06/2019 12:53 PM, Noel Chiappa via cctalk wrote: If so, i) we're down to one problem (good news), and our problem turns into finding out how that section of the code got trashed (bad news). I'm thinking it is bad memory. It seems unlikely bus problems could alter only ONE BIT per word, so I think it is just a bad memory chip, and finding multiple words where the 01 bit is now turned on sure looks like that kind of problem. It could, of course, be a bad driver or receiver on the memory board. Might also check the other voltage in the memory array (+12 or whatever was used internally in the particular memory) and also look for degraded caps on the board. Jon
Re: PDP-11/45 RSTS/E boot problem
On 02/06/2019 04:24 PM, Brent Hilpert via cctalk wrote: On 2019-Feb-06, at 1:21 PM, Noel Chiappa via cctalk wrote: From: Brent Hilpert what about the refresh circuitry of the memory board? ... It might also explain why a number of 4116s were (apparently) failing earlier in the efforts ... replacing them might have just replaced them with 'slightly better' chips, i.e. with a slightly longer refresh tolerance. Ooh, excellent idea! Is the schematic available for the memory board at-issue? Curious myself to see what approach for refresh DEC used. Hmm, yes, if the refresh is done by one-shots and RC timing, a failed cap could silently kill the refresh trigger. An easy way to check is put something in a few locations and halt the CPU for some time (seconds to minutes). If the content is now gone, then the refresh is very likely not being done. Jon
Re: PDP-11/45 RSTS/E boot problem
On 02/06/2019 05:39 PM, Fritz Mueller via cctalk wrote: On Feb 6, 2019, at 2:24 PM, Brent Hilpert via cctalk wrote: Is the schematic available for the memory board at-issue? Curious myself to see what approach for refresh DEC used. Yes, here: http://bitsavers.trailing-edge.com/pdf/dec/pdp11/memory/MP00672_MS11L_engDrw.pdf There is also a technical manual adjacent, with circuit descriptions. I will scope this up tonight and take a look! Yup, page 6, a 555 RC refresh timer! Jon
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2019-Feb-06, at 4:19 PM, Chuck Guzis via cctalk wrote: > On 2/6/19 2:29 PM, Brent Hilpert via cctalk wrote: > >> (I take it you mean "now look at the -left- side".) > > Well, you know, my *other* right... :) > >> However, looking at my 7970A, it appears you could separate the cast-Al >> transport frame from the chassis box >> by unscrewing the 4 exterior left-side hinge screws, as well as detaching >> all the cabling between them involving >> a wire harness and a dozen-or-so plugs. > > Swing the drive assembly out from the back cover--you'll note that the > pivot points on the two hinges are about 1" away from the cover flange. > You've got plenty of room to drill your mounting holes from the *rear* > of that flange. You might even have enough clearance for a > countersink--but that may not be necessary--the frame casting only > extends in from the left about a half-inch--you may even clear some > oval-headed screws or get away with some truss-head screws. > Alternatively, could mill a slight relief in the casting to clear the heads. > > I think it's doable without removing the drive from the cover. Granted you could drill the holes from the rear of the flange, however from what I can see the hinge design doesn't look like it will allow the transport frame to swing far enough to clear access for the screwdriver shaft to tighten the screws from the front (might swing to around 110deg, but not to 170-180). The 2-1/2" thick transport frame pivots near the middle of it's thickness, at 90deg half the thickness is still well across the flange. You'd need a ~ < 1" clearance right angle screwdriver to fit between the flange and the transport frame, or bolt head screws and box wrench which then necessitates the milling of clearance for the heads out of the cast frame. I might consider the transport removal approach next time I have to mount mine - even though I have the proper mounting bracket - just to split the weight up. I did once do a one-person free-lift mount of the thing, but that was about 20 years ago. >> For loading concerns raised by Jay, in both cases (designed-for steel >> bracket vs drilled flange) the weight of the drive ends up being >> borne by 4 rack-screws on the left and 3 on the right. The difference >> would be steel vs Al bearing down on the 4 screws on the left, and >> some altered bending moments on the left side of the Al chassis box >> around the flange, offhand I wouldn't think it would matter. > > I tend to agree--the force is mostly downward on the front of the drive. > I suppose that you could reinforce the aluminum housing with some steel > bar backing up the mounting flanges, but that seems like overkill to me.
Re: PDP-11/45 RSTS/E boot problem
On 2/6/19 6:25 PM, Jon Elson via cctalk wrote: I'm thinking it is bad memory. It seems unlikely bus problems could alter only ONE BIT per word, so I think it is just a bad memory chip, and finding multiple words where the 01 bit is now turned on sure looks like that kind of problem. So, there was an issue specifically relating to bit 12 on the front panel (d'oh!), which I have now cleared up. Furthermore, the "authoritative" sequence of 16 words obtained from the front panel last night, after addressing this issue, is: PA:171600: 016162 004767 000224 000414 016700 016152 016702 016144 PA:171620: 004767 000206 000405 012404 012467 016124 000167 177346 ...and, as it turns out, this exact sequence also occurs within the ls binary, on disk (per "od"): 0004220 016162 004767 000224 000414 016700 016152 016702 016144 0004240 004767 000206 000405 012404 012467 016124 000167 177346 So, the memory there _seems_ fine with the latest info at our disposal. It looks like the question boils down to either "how did that part of the binary get to that part of memory?", or "how did we end up executing out of that part of memory?" Could still be a memory issue _elsewhere_ that lands us there, of course... Could also be a translation error lurking in the KT11, or a CPU bug not found by any of the DEC diagnostic suites. I will scope the refresh clock when I get home tonight, and I'm planning on hauling out the logic analyzer for an IR trace this weekend... --FritzM. P.S. One idea that popped into my head recently, after a suggestion here to check the KT11 address translation adders, and my response "but the diagnostics!"... A bug in one of the carry lookahead generators used between the bit slices of that adder could cause a mistranslation on only a fairly selective subset of virtual addresses, and this might conceivably be missed by the KT11 diagnostics? *IF* that's the case and we can chase the IR trace upstream to the place of an unlucky mistranslation, it will be pretty easy to track down then in the hw and fix.
Re: PDP-11/45 RSTS/E boot problem
> From: Jon Elson > I'm thinking it is bad memory. ... I think it is just a bad memory chip Nothing so simple, I'm afraid! The memory actually contains: PA:171600: 016162 004767 000224 000414 016700 016152 016702 016144 and it's _supposed_ to be holding: PA:171600: 110024 010400 000167 16 010500 010605 010446 010346 This together with Fritz's discovery of that first 'bad memory' pattern _elsewhere_ in the binary for the command makes it look pretty likely that some sort of other error has wound up with stuff being put in the wrong location. Noel
GSX-80 software
I'm wondering if anyone knows of any CP/M software using GSX-80, which could be an interesting demo, or game. I have found Kasekastchen ( http://atariage.com/forums/topic/244781-kaesekaestchen-a-new-gsx-based-game-for-pcw-cpc-and-other-cpm-machines/) (misspelled without accents to make the mailman happy), but it mostly just freezes after loading GSX-80 on my TS-803 so far (under the 'remote processor' version of the OS at least). Thanks, Pat
Re: PDP-11/45 RSTS/E boot problem
> From: Fritz Mueller > It looks like the question boils down to either "how did that part of > the binary get to that part of memory?", or "how did we end up > executing out of that part of memory?" More the former, I think. UISA0 contains 001614, and physical memory at 0161400 does contain the first few instructions of the command's binary, so that 01614 is probably correct for the base address of segment (page) 0, which contains all the code for the command. (Without looking through the OS's guts, I can't confirm, from interal data structures, that that's where it decided to put the command's binary.) The PC at fault time is 010210, which is correct for the frame setup function, CSV; and looking at the contents of the stack, registers etc makes it pretty certain it had just done the "JSR R5, CSV" to get there. And 0161400 + 010210 = 0171610, which contains something completely different from what's in the command binary at 010210! > Could still be a memory issue _elsewhere_ that lands us there, of > course... Could also be a translation error lurking in the KT11, or a > CPU bug not found by any of the DEC diagnostic suites. Yup. Like I said, good news is we're down to one problem; bad news is it's a Duesie! Noel
Re: PDP-11/45 RSTS/E boot problem
It looks like the question boils down to either "how did that part of the binary get to that part of memory?", or "how did we end up executing out of that part of memory?" More the former, I think... Noel, is it possible for you deduce where Unix _should_ be placing these "bad" bits (from file offset octal 4220)? Maybe a comparison of addresses where the bits should be, with addresses where the "bad" copy ends up, could point us at some particular failure modes to check in the KT11, CPU, or RK11... --FritzM.
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2/6/19 6:33 PM, Brent Hilpert via cctalk wrote: > Granted you could drill the holes from the rear of the flange, > however from what I can see the hinge design doesn't look like it > will allow the transport frame to swing far enough to clear access > for the screwdriver shaft to tighten the screws from the front (might > swing to around 110deg, but not to 170-180). The 2-1/2" thick > transport frame pivots near the middle of it's thickness, at 90deg > half the thickness is still well across the flange. You'd need a ~ < > 1" clearance right angle screwdriver to fit between the flange and > the transport frame, or bolt head screws and box wrench which then > necessitates the milling of clearance for the heads out of the cast > frame. Nah, there's plenty of room to get a screwdriver in there. I've had much tighter spots. --Chuck
Re: PDP-11/45 RSTS/E boot problem
> 4116 datasheet specs 2mS, my calcs give a refresh period of 1.5mS, the 14.5uS > from the manual would give 1.86 mS, 7% shy of 2. > The schematic specs 1% resistors, and the parts list does appear to spec a > high-tolerance "1%200PPM" cap. > > Although there are the internal voltage divider Rs in the 555 which are also > critical for the timing and everything is 40+ years old. > > Idle speculation at my distance, we'll see what Fritz observes. Brent: 11.8us, 6.4us position Manual: 14.5us, 6.0us positive Actual: 15.2us, 8.5us positive So yeah, a little pokey there...
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2019-Feb-06, at 7:48 PM, Chuck Guzis via cctalk wrote: > On 2/6/19 6:33 PM, Brent Hilpert via cctalk wrote: > >> Granted you could drill the holes from the rear of the flange, >> however from what I can see the hinge design doesn't look like it >> will allow the transport frame to swing far enough to clear access >> for the screwdriver shaft to tighten the screws from the front (might >> swing to around 110deg, but not to 170-180). The 2-1/2" thick >> transport frame pivots near the middle of it's thickness, at 90deg >> half the thickness is still well across the flange. You'd need a ~ < >> 1" clearance right angle screwdriver to fit between the flange and >> the transport frame, or bolt head screws and box wrench which then >> necessitates the milling of clearance for the heads out of the cast >> frame. > > > Nah, there's plenty of room to get a screwdriver in there. I've had > much tighter spots. Well, maybe they changed the hinge design slightly for the model you're looking at. Here are some pics of the 7970A with the transport open at 90 deg: http://madrona.ca/tmp/HP7970A/hingeTop.jpg http://madrona.ca/tmp/HP7970A/hingeInt.jpg http://madrona.ca/tmp/HP7970A/hingeExt.jpg That's about 1-1/4" between the flange and the cast frame. There's no way you're angling a regular shafted screwdriver in there to adequately tighten screws. One could undo the catch that limits the angle of swing, but I still don't expect it's going to swing far enough to get the frame out of the way, let alone the PCBs and motors still in the way. (The black part next to the Al flange is the 'proper' steel mounting bracket.) Flat-head hex bolts with a shortened allen-key could do it, as long as the tensional strength of the screw-heads was adequate.
Re: PDP-11/45 RSTS/E boot problem
On 2019-Feb-06, at 10:37 PM, Fritz Mueller via cctalk wrote: >> 4116 datasheet specs 2mS, my calcs give a refresh period of 1.5mS, the >> 14.5uS from the manual would give 1.86 mS, 7% shy of 2. >> The schematic specs 1% resistors, and the parts list does appear to spec a >> high-tolerance "1%200PPM" cap. >> >> Although there are the internal voltage divider Rs in the 555 which are also >> critical for the timing and everything is 40+ years old. >> >> Idle speculation at my distance, we'll see what Fritz observes. > > Brent: 11.8us, 6.4us position > Manual: 14.5us, 6.0us positive > Actual: 15.2us, 8.5us positive > > So yeah, a little pokey there... 15.2uS gives a 1.95mS refresh, so it's awfully close to the 2mS spec, but still within. The datasheet I was looking at doesn't seem to give any spec for tolerance on the refresh so one would guess there's a safety margin built into the 2mS spec. Seems a little less-likely to be the problem, given(?) as well that you have fairly consistent (is deterministic overstating it?) behaviour. If you wanted to test it by experiment, without having to remove the installed Rs, you could test-clip another R in parallel with the 38.4K, probably something around 200K, to shorten the 555 period.
Re: Mounting HP7970e 9-Trk 1/2" Tape Drive
On 2/6/19 10:42 PM, Brent Hilpert via cctalk wrote: > Well, maybe they changed the hinge design slightly for the model you're > looking at. > Here are some pics of the 7970A with the transport open at 90 deg: > http://madrona.ca/tmp/HP7970A/hingeTop.jpg > http://madrona.ca/tmp/HP7970A/hingeInt.jpg > http://madrona.ca/tmp/HP7970A/hingeExt.jpg > > That's about 1-1/4" between the flange and the cast frame. > There's no way you're angling a regular shafted screwdriver in there to > adequately tighten screws. > One could undo the catch that limits the angle of swing, but I still don't > expect it's going to swing far > enough to get the frame out of the way, let alone the PCBs and motors still > in the way. > > (The black part next to the Al flange is the 'proper' steel mounting bracket.) > > Flat-head hex bolts with a shortened allen-key could do it, as long as the > tensional strength of the screw-heads was adequate. Looking at it, it may be easier to do with a regular screwdriver if the drive is opened at 45 degrees rather than 90. Ratchet right-angle screwdrivers are also an option, as are ball-end allen wrenches or offset-head screwdrivers. None are particularly dear. In any case, as I've said, I'm not about to hoist my 7970 into a rack. I lost enough skin just getting it out of the truck into the shop. I may, however, go prowling for a lowboy EIA rack... --Chuck
Re: PDP-11/45 RSTS/E boot problem
> Seems a little less-likely to be the problem, given(?) as well that you have > fairly consistent (is deterministic overstating it?) behaviour. Yeah. We've gotten to the point now where enough layered problems have been cleared away that the remaining behavior is quite deterministic. > If you wanted to test it by experiment, without having to remove the > installed Rs, you could test-clip another R in parallel with the 38.4K, > probably something around 200K, to shorten the 555 period. Yes; and I think a quick solder tack for that would even be easier to manage than clips in there. Will give that a go this weekend. cheers, --FritzM.
