Re: 21MX proms (per request
On Sun, Sep 13, 2015 at 7:44 PM, J. David Bryan wrote: > On Sunday, September 13, 2015 at 8:42, Jay West wrote: > >> 3) Any I/O instructions in the loader are automatically patched during >> the transfer (based on switch register bits 11 through 6) so that the >> correct I/O address (device) is referenced. > > It's actually a bit more nuanced than this. What occurs is: > > 3a) Except for halt instructions, any I/O instruction referencing select > code 10 (octal) or greater is patched by adding the select code > value in the switch register minus 10. > > This means that (a) halt instructions, which are in the I/O group, are not > altered, (b) DCPC I/O instructions, which reference select codes 2, 3, 6, > or 7 are not altered, and (c) interfaces that use two select codes, e.g., > the 7900 disc interface, get both select codes updated properly. It also > implies that all loaders are written to reference select code 10 (or 10 and > 11, etc.). > > 3b) The two's-complement of the memory address of the first word of the > loader is stored in the last word in memory. > > This is so that loaders can check that what they are loading does not > overwrite the loader itself. For example, the paper tape loader does a HLT > 55 if the absolute binary tape contains a record that would overlay the > loader executable code. > > 3c) The contents of the penultimate memory location is patched by adding > the select code value in the switch register minus 10. > > This is used to patch the select code into an optional DCPC control word, > which is a constant and not an I/O instruction and so wouldn't be patched > by (3a). Loaders that use DCPC, e.g., the disc loaders, place their DCPC > control word at this location. > > There's actually quite a lot going on under the hood for that IBL button > press. > > -- Dave > For the curious the source code for the Initial Binary Loader microcode is listed on pages D-16 and D-17 of this manual: http://www.bitsavers.org/pdf/hp/1000/1000_MEF_EngrRef/92851-90001_Mar81_1.1.pdf It is reasonably well commented, but still not completely obvious exactly what and why it is doing what it is doing without something like Dave's explanation above.
RE: 21MX proms (per request
Dwight wrote... My main thinking was the best place to save a boot is to save it on paper.I recall looking at mine to see how the flag worked.( not mass storage yet so needed a serial loader ). - Ah, gotcha. Yep, you're right! On a few loaders where the part #'s were obscured, I had to do exactly that (disassemble first handful of instructions to see which one it was). Best, J
RE: 21MX proms (per request
On Sunday, September 13, 2015 at 8:42, Jay West wrote: > 3) Any I/O instructions in the loader are automatically patched during > the transfer (based on switch register bits 11 through 6) so that the > correct I/O address (device) is referenced. It's actually a bit more nuanced than this. What occurs is: 3a) Except for halt instructions, any I/O instruction referencing select code 10 (octal) or greater is patched by adding the select code value in the switch register minus 10. This means that (a) halt instructions, which are in the I/O group, are not altered, (b) DCPC I/O instructions, which reference select codes 2, 3, 6, or 7 are not altered, and (c) interfaces that use two select codes, e.g., the 7900 disc interface, get both select codes updated properly. It also implies that all loaders are written to reference select code 10 (or 10 and 11, etc.). 3b) The two's-complement of the memory address of the first word of the loader is stored in the last word in memory. This is so that loaders can check that what they are loading does not overwrite the loader itself. For example, the paper tape loader does a HLT 55 if the absolute binary tape contains a record that would overlay the loader executable code. 3c) The contents of the penultimate memory location is patched by adding the select code value in the switch register minus 10. This is used to patch the select code into an optional DCPC control word, which is a constant and not an I/O instruction and so wouldn't be patched by (3a). Loaders that use DCPC, e.g., the disc loaders, place their DCPC control word at this location. There's actually quite a lot going on under the hood for that IBL button press. -- Dave
RE: 21MX proms (per request
Dwight wrote... > If you still have a working machine, why not disassemble the boot ROMs. They are only a few instructions long. Not necessary, as the source and binary for all the loader roms is in the aforementioned manual. None of them are "only a few instructions long". Most of them are a couple pages of assembler code. > As I recall, in the boot sequence, it transfers the ROMs to ram and then executes it. Pressing the IPL/TEST button does the following: 1) It executes cpu diagnostic 1 (registers and a few functions) and 2 (quick memory test, up to 32kw) that are stored in microcode. 2) It transfers any one of the four installed loader roms (as designated by switch register bits 15 & 14) to the last (up to 32kw) 64 words of memory. 3) Any I/O instructions in the loader are automatically patched during the transfer (based on switch register bits 11 through 6) so that the correct I/O address (device) is referenced. 4) The program counter is set to the first word of the last (up to 32kw) 64 words. Then you can hit the run switch to execute the (patched) loader. Interesting to me... on the 2100A/S, the last 64 words of memory can be protected. They cannot be accessed unless the "loader enable" button/light has been pressed. This makes it less likely that your loader (which had to be hand entered on that model as it didn't support "loader roms") would accidentally be clobbered by other code. The loader enable button stays on until the computer reaches a halt instruction or the halt button is pressed. So the typical process was to set the program counter to the first word of the last 64 words (up to 32kw) of memory, press loader enable, then run. Once the loader finished loading whatever it's target was, it would halt (thus re-protecting the loader). Then the user could press run to execute the target code and not worry about the loader getting toasted. Best, J
RE: 21MX proms (per request
> From: jw...@classiccmp.org > > Dwight wrote... > > If you still have a working machine, why not disassemble the boot ROMs. > They are only a few instructions long. > Not necessary, as the source and binary for all the loader roms is in the > aforementioned manual. None of them are "only a few instructions long". Most > of them are a couple pages of assembler code. > > > As I recall, in the boot sequence, it transfers the ROMs to ram and then > executes it. > Pressing the IPL/TEST button does the following: > 1) It executes cpu diagnostic 1 (registers and a few functions) and 2 (quick > memory test, up to 32kw) that are stored in microcode. > 2) It transfers any one of the four installed loader roms (as designated by > switch register bits 15 & 14) to the last (up to 32kw) 64 words of memory. > 3) Any I/O instructions in the loader are automatically patched during the > transfer (based on switch register bits 11 through 6) so that the correct > I/O address (device) is referenced. > 4) The program counter is set to the first word of the last (up to 32kw) 64 > words. > Then you can hit the run switch to execute the (patched) loader. > > Interesting to me... on the 2100A/S, the last 64 words of memory can be > protected. They cannot be accessed unless the "loader enable" button/light > has been pressed. This makes it less likely that your loader (which had to > be hand entered on that model as it didn't support "loader roms") would > accidentally be clobbered by other code. The loader enable button stays on > until the computer reaches a halt instruction or the halt button is pressed. > So the typical process was to set the program counter to the first word of > the last 64 words (up to 32kw) of memory, press loader enable, then run. > Once the loader finished loading whatever it's target was, it would halt > (thus re-protecting the loader). Then the user could press run to execute > the target code and not worry about the loader getting toasted. > > Best, > > J My main thinking was the best place to save a boot is to save it on paper.I recall looking at mine to see how the flag worked.( not mass storage yet so needed a serial loader ).Dwight
RE: 21MX proms (per request
If you still have a working machine, why not disassemble the boot ROMs. They are only a few instructions long. Making a listing for the 21MX makes it easy to check them from the front panel. As I recall, in the boot sequence, it transfers the ROMs to ram and then executes it. Dwight
Re: 21MX proms (per request
On Fri, Sep 11, 2015 at 12:41 PM, GerardCJAT wrote: > HOW OFTEN theses old PROM fail ?? Note that some bipolar PROMs suffer from fuse regrowth, where bits that have been programmed gradually revert to an unprogrammed state. This was a big problem with NiCr fuses. Later bipolar PROMs used different fuse materials; TiW was one of the later choices. I don't know whether TiW or other newer fuses have regrowth issues, but if they do, it's slower than NiCr. It is possible to recover the bits from a bipolar PROM with regrowth by decap and optical inspection, because the regrowth happens in relatively narrow tendrils which are visibly different than an unprogrammed fuse. I've actually seen that done. There is speculation that it could be done without decap by trying to blow each unblown fuse and measuring the energy required to blow the fuse; a regrown one should require less energy. I'm not aware of anyone actually having done it that way. I wouldn't trust a one-of-a-kind PROM to that process. Obviously it's best to dump the PROM contents before regrowth becomes an issue.
RE: 21MX proms (per request
Gerard wrote HOW OFTEN theses old PROM fail ?? Who had been through this problem and does it "really" worth to have some blanks "just in case" ?? 1) Once is enough, if it is the only known copy of that particular rom. But in general they are very reliable. More often than not - when they fail - something else took them out in the process of it's failure. I have had a prom failure all by itself though. 2) It's extremely worth it. For one many of the machines run by people on this list immediately become boatanchors if a prom fails, especially if it's a microcode rom. Second... you're missing the more general case - say I have a HP21MX that was running 2000/Access and I now want to run RTE-6/VM. Guess what - I need the microcode roms that are required for RTE-6/VM. Fortunately, other collectors have taken the time to copy their proms and upload them online (bitsavers is a great example). So I can download their rom images and burn a new set for running new software I had not been able to run before. Another example - say my machine came with only paper tape. Two years later I happen to acquire a disc drive. Sure would be nice if I could just download the loader rom image and burn it so that I can boot from that device. With a burner and blanks, all that is possible. Best, J
RE: 21MX proms (per request
That triggers again a question I had for a while ... HOW OFTEN theses old PROM fail ?? Who had been through this problem and does it "really" worth to have some blanks "just in case" ?? --- L'absence de virus dans ce courrier électronique a été vérifiée par le logiciel antivirus Avast. https://www.avast.com/antivirus
RE: 21MX proms (per request
I was mistaken. I've admitted it. Dwight > From: a...@p850ug1.demon.co.uk > To: cctalk@classiccmp.org > Subject: RE: 21MX proms (per request > Date: Thu, 10 Sep 2015 19:15:42 + > > > As often the case, I recall wrong. > > I stand corrected. > > Dwight > > > > From: dkel...@hotmail.com > > To: cctalk@classiccmp.org > > Subject: RE: 21MX proms (per request > > Date: Thu, 10 Sep 2015 12:09:39 -0700 > > > > > > > > > > Yep, looked it up. > > 2716 and 2732 used a pulsed Vpp( 2708 a well ). > > Beyond that they had a static Vpp and a PGM pin. > > Dwight > > I am now totally confused. Do you believe the 2716 and 2732 require a Vpp > pulse for each > location or not? > > FWIW, I believe they do not (confirmed by the data sheets I have found on the > web). You can > apply Vpp to get the thing into program mode and then apply a TTL-level 50ms > pulse to > program a location. > > -tony
RE: 21MX proms (per request
> As often the case, I recall wrong. > I stand corrected. > Dwight > > From: dkel...@hotmail.com > To: cctalk@classiccmp.org > Subject: RE: 21MX proms (per request > Date: Thu, 10 Sep 2015 12:09:39 -0700 > > > > > Yep, looked it up. > 2716 and 2732 used a pulsed Vpp( 2708 a well ). > Beyond that they had a static Vpp and a PGM pin. > Dwight I am now totally confused. Do you believe the 2716 and 2732 require a Vpp pulse for each location or not? FWIW, I believe they do not (confirmed by the data sheets I have found on the web). You can apply Vpp to get the thing into program mode and then apply a TTL-level 50ms pulse to program a location. -tony
RE: 21MX proms (per request
Yep, looked it up. 2716 and 2732 used a pulsed Vpp( 2708 a well ). Beyond that they had a static Vpp and a PGM pin. Dwight
RE: 21MX proms (per request
As often the case, I recall wrong. I stand corrected. Dwight From: dkel...@hotmail.com To: cctalk@classiccmp.org Subject: RE: 21MX proms (per request Date: Thu, 10 Sep 2015 12:09:39 -0700 Yep, looked it up. 2716 and 2732 used a pulsed Vpp( 2708 a well ). Beyond that they had a static Vpp and a PGM pin. Dwight
Re: 21MX proms (per request
- Original Message - From: "tony duell" To: "General Discussion: On-Topic and Off-Topic Posts" Sent: Thursday, September 10, 2015 2:29 PM Subject: RE: 21MX proms (per request Your right, I didn't say that the 2716 was not a single rail, just that it didn't have a separate Vpp and PGM pin. It was programmed by turning Vpp on and off. I could be wrong that the 2732s were that way as well. The data sheet for the SGS-Thomson 2716 here : http://ee-classes.usc.edu/ee459/library/datasheets/2716.pdf says that you apply Vpp and keep it applied, set up address and data (with G/, pin 20, more commonly called output enable, high and E/P low) and then program each location by taking the E/P pin (Pin 18, more commonly called chip enable) high for 50ms. That is what I remember doing. You didn't have to pulse Vpp. -tony = - Reply - Yup; I still have a 2716 programmer I cobbled together for my PET and it just has a manual DIP switch (and LED) to turn Vpp on/off.before and after programming. To be sure, there were different versions but none pulsed Vpp AFAIK. m
RE: 21MX proms (per request
> > Your right, I didn't say that the 2716 was not a single rail, just that it > didn't have a separate Vpp and PGM pin. It was programmed by turning > Vpp on and off. I could be wrong that the 2732s were that way as well. The data sheet for the SGS-Thomson 2716 here : http://ee-classes.usc.edu/ee459/library/datasheets/2716.pdf says that you apply Vpp and keep it applied, set up address and data (with G/, pin 20, more commonly called output enable, high and E/P low) and then program each location by taking the E/P pin (Pin 18, more commonly called chip enable) high for 50ms. That is what I remember doing. You didn't have to pulse Vpp. -tony
RE: 21MX proms (per request
> From: a...@p850ug1.demon.co.uk > To: cctalk@classiccmp.org > Subject: RE: 21MX proms (per request > Date: Thu, 10 Sep 2015 14:14:44 + > > > 2716 are that last of the program by turning the programming voltage > > on and off. > > I must be mis-remembering how I designed my first EPROM programmer. I > know I could do 2716s (single-rail, not the TI ones) and I thought I always > applied Vpp and pulsed another pin at TTL levels to program them > > IIRC the 27128 was the last one to actually allow the 'dumb' 50ms > programming algorithm. It may well work on larger chips, but > I never tried it. That's why I designed my programmer to do > 2716s, 2732s, 2764s and 27128s only. Not having another > programmer I couldn't use a microprocessor or microcontroller > (no way to load the firmware) so I had to do it all in TTL logic. > Doing the 'intellegent' algorithm in TTL was a bit much ;-) > > -tony Your right, I didn't say that the 2716 was not a single rail, just that it didn't have a separate Vpp and PGM pin. It was programmed by turning Vpp on and off. I could be wrong that the 2732s were that way as well. The TI 2716s were not so friendly. Intel sold half bad 2716s for 5 volt 2508s. Even after 2716s price dropped, they still sold 2708s for $32 when you could buy a 2716 for $3 to $4. Dwight
Re: 21MX proms (per request
On 9/10/15 7:14 AM, dwight wrote: Anyone interested in doing 1702As should look at the schematic in the MCS4 user manual on bitsavers.org or just buy a ME1702A from Martin Eberhard
RE: 21MX proms (per request
> 2716 are that last of the program by turning the programming voltage > on and off. I must be mis-remembering how I designed my first EPROM programmer. I know I could do 2716s (single-rail, not the TI ones) and I thought I always applied Vpp and pulsed another pin at TTL levels to program them IIRC the 27128 was the last one to actually allow the 'dumb' 50ms programming algorithm. It may well work on larger chips, but I never tried it. That's why I designed my programmer to do 2716s, 2732s, 2764s and 27128s only. Not having another programmer I couldn't use a microprocessor or microcontroller (no way to load the firmware) so I had to do it all in TTL logic. Doing the 'intellegent' algorithm in TTL was a bit much ;-) -tony
RE: 21MX proms (per request
I would be surprised if it did 1702s and 2708s. Even 2716s have a slightly different hardware configuration. 1702s require voltages like 50 volts ( I could be a little off ) and changing address and data lines over wide voltage ranges. 2708s require multiple rail voltages as well as programming voltages. 2716 are that last of the program by turning the programming voltage on and off. All the newer chips have a constant programming voltage and a separate program logic level pin. They can even be read while the programming voltage is high. I doubt any would make the special provisions for 1702s. 2708s are a stretch but if your not doing 2716s it won't be able to handle 2708 even if it had the extra rail voltages. I have a DataIO ( I think a 29B ) and I know it doesn't do 1702s. In any case, I don't think any of these would be fast enough for a 21MX boot code. I think these expect it to be faster than 100ns. Dwight
RE: 21MX proms (per request
Glen wrote... Just in case anyone is looking at BP Microsystems programmers: I'm looking - heck, at that price, a good backup/insurance policy! Would love to see a full device list J
Re: 21MX proms (per request
On Wed, Sep 9, 2015 at 4:46 PM, Jay West wrote: > > Another good example - the CP-1128 appears to require a usb attached computer > to function. Just in case anyone is looking at BP Microsystems programmers: As far as I know only their first programmer the EP-1 had a RS-232 interface. After that they all had an LPT interface (PLD-1100, PLD-1128, EP-1132, EP-1140, CP-1128, BP-1148, BP-1200, BP-1400, BP-1600, BP-1700) until they switched to a USB interface (BP-1410, BP-1610, BP-1710). The last software update for the LPT interface BP-1200 and BP-1400 was in 2008 and for the BP-1600 and BP-1700 was in 2013. Only the USB interface models are supported by current software updates. I got a USB interface BP-1410 on eBay a year or so ago but I almost never see the USB interface models there. -Glen
Re: 21MX proms (per request
On Wed, Sep 9, 2015 at 1:20 PM, Jay Jaeger wrote: > > Anybody know if the CP-1128 supports any of the older EProms (2708, 2716 > or 1702)? I couldn't find a device list online. > > JRJ As far as I know no BP Microsystems programmers supported 1702 or 2708 EPROMs. The last version of the programming software which supported the CP-1128 was BPSoft-03 (DOS) or BPWSoft-03 (Windows) released in October 2003. You can still download those legacy versions. You have to register a user id and password first, which is free, but annoying. You can search for supported devices when you run the software in demo mode without a programmer connected. The CP-1128 supports a variety of 2716 parts. I would paste the supported list here but the device chooser in the software doesn't allow a text copy of the selection list. I could paste it as a screen capture in direct email off list for 2716 parts if you're curious. -Glen
RE: Re: 21MX proms (per request)
Marc wrote But I want to keep my machine original and vintage if I reasonably can. My programmer [snip] fits perfectly in my collection of higher end, historically meaningful engineering tools. Agreed. I was the same way when selecting a logic analyzer. Given my penchant for a certain period of HP gear, I got a 1631D. Sure, there are probably lots better LA's out there. But it was an HP of the right period and fully capable for what I needed :) J
RE: 21MX proms (per request
Sean wrote... -- my bench is all Racal, Tek, HP, Fluke, etc and the -- You must be one of those high net worth folks you mentioned in your previous post, I'm jealous of that kind of bench gear! I'm not saying the CP-1128 isn't a great value. Of course it's a good solution! I am merely saying the Data I/O 29B currently and has been a good value (in response to your post saying it was "too expensive for 30+ year old gear"). But since it was brought up, here's some things to consider The Data I/O 29B is specifically sought out by arcade enthusiasts (and many vintage computer collectors that I know) because it supports an unusually wide array of vintage chips, most that we're likely to come across. Why is that important, if the CP-1128 does - as glen points out - program a subset of the needed (for this specific case) chips? Answer from past experience There may be a dozen chips that will work for the HP 1K loader roms. What I have found over the past many years is that the supply ebbs and flows. Good example - for about a year, MMI 6301's were unobtainium. All the suppliers I could find were all pushing the Harris 7611's, because they couldn't get the 6301's either. Then a year later, apparently a batch of fuji 7114's were found and those were available, because suppliers couldn't find any more 7611's (at the time). Now I'm finding the MMI 6301's again. Yes, these chips are all compatible once programmed, but some programmers will do one and not the other. This "ebb and flow" in supply may occur right at the least convenient time, like when your 2000/Access IOP firmware chips die (me, about two months ago). If your programmer supports the widest possible selection of chips, even post-programmed compatibles, you're in a better spot. If not, a post-programmed compatible chip may well be available, but your programmer doesn't support it. Not a great spot. My 29B will also do a lot more different types of devices than usual, thanks to the plethora of other adapters (not just unipak 2B) that came with mine. Another good example - the CP-1128 appears to require a usb attached computer to function. While I usually connect my 29B to a computer to program (via serial), there are a few occasions when I've been exceedingly glad that it can be fully operated from the built in control panel without having to have a computer to run it. Another example - Some manufacturers, over time, drop support for very early devices. That can't happen with the 29B ;) It sure can and does happen with current devices being manufactured. There's a downside of course... just try finding replacement parts for a 29b ;) Fortunately, schematics exist. Long story short, as I said before, there's a reason that programmer still holds a high value. For some people, those reasons are worth it. For others, they are not. Is the 29B "the best" programmer? Probably not, as "best" is both situational and subjective. I'm willing to allocate portions of my precious small bench gear budget for the above reasons. But several folks asked at the same time for advice on 21MX M/E/F proms and programmers, and that post was my advice. There are certainly other great programmers out there. Best, J
RE: Re: 21MX proms (per request)
Absolutely (assuming you count your engineering time as free), not to mention it feels rewarding to use clever engineering tricks to solve a problem instead of money. But I want to keep my machine original and vintage if I reasonably can. My programmer ended up very reasonably priced, and it is recognized as one of the better vintage programmers of that era. So it fits perfectly in my collection of higher end, historically meaningful engineering tools. Two birds with one stone, so it was a pretty easy decision. Marc >Sean Caron : >The median listing price for them on eBay for a 29B with pack seems to be around $3-400 which IMO is a little steep for a 30+ year >old PROM programmer. Hopefully your best offer successfully accepted was much lower! >I think the part cost on the PROMs pales in comparison. For the cost of the 29B, you could design a replacement for the original >PROM, have some boards fabricated, stuff them and you'd still be ahead a few hundred bucks ... >starts to make sense at those kind of prices, imo. >Best, >Sean
Re: 21MX proms (per request
On 9/8/2015 9:38 PM, Glen Slick wrote: > On Tue, Sep 8, 2015 at 1:19 PM, Sean Caron wrote: >> The median listing price for them on eBay for a 29B with pack seems to be >> around $3-400 which IMO is a little steep for a 30+ year old PROM >> programmer. Hopefully your best offer successfully accepted was much lower! >> I think the part cost on the PROMs pales in comparison. > > You can currently buy a BP Microsystems CP-1128 for $38.50 shipped on eBay: > http://www.ebay.com/itm/181853494660 > Anybody know if the CP-1128 supports any of the older EProms (2708, 2716 or 1702)? I couldn't find a device list online. JRJ
Re: 21MX proms (per request
Well, we all have differing levels of electronics knowledge ... and net worth... which tip the calculus one way or the other depending on the one's personal situation... As much as I do wish money could be no object, that's not realistic for me. Best, Sean On Tue, Sep 8, 2015 at 5:39 PM, Jay West wrote: > Sean wrote > -- > The median listing price for them on eBay for a 29B with pack seems to be > around $3-400 which IMO is a little steep for a 30+ year old PROM > programmer. > -- > Nope. There is a very good reason why they still command such a price. > Worth every penny. > > I can't belittle a 30 year old piece of test equipment no more than I > could a similarly aged computer :) > > J > > >
Re: 21MX proms (per request
And I do love and appreciate the old, built-to-last-a-lifetime test equipment ... my bench is all Racal, Tek, HP, Fluke, etc and the median age is probably at least 25 years but, I mean, $400 is almost halfway to a nice used spectrum analyzer and I know which I'd rather have :O Choices, choices... Best, Sean On Tue, Sep 8, 2015 at 6:17 PM, Sean Caron wrote: > Well, we all have differing levels of electronics knowledge ... and net > worth... which tip the calculus one way or the other depending on the one's > personal situation... As much as I do wish money could be no object, that's > not realistic for me. > > Best, > > Sean > > > On Tue, Sep 8, 2015 at 5:39 PM, Jay West wrote: > >> Sean wrote >> -- >> The median listing price for them on eBay for a 29B with pack seems to be >> around $3-400 which IMO is a little steep for a 30+ year old PROM >> programmer. >> -- >> Nope. There is a very good reason why they still command such a price. >> Worth every penny. >> >> I can't belittle a 30 year old piece of test equipment no more than I >> could a similarly aged computer :) >> >> J >> >> >> >
Re: 21MX proms (per request
On Tue, Sep 8, 2015 at 1:19 PM, Sean Caron wrote: > The median listing price for them on eBay for a 29B with pack seems to be > around $3-400 which IMO is a little steep for a 30+ year old PROM > programmer. Hopefully your best offer successfully accepted was much lower! > I think the part cost on the PROMs pales in comparison. You can currently buy a BP Microsystems CP-1128 for $38.50 shipped on eBay: http://www.ebay.com/itm/181853494660 For the HP 21MX PROMs being discussed it supports at least the following: 256x4 tri-state output AM27S21 DM74S287 82S129 / 82S129A 512x8 tri-state output AM27S31 DM74S474 82S141 1024x8 tri-state output AM27S181 82S181 / 82S181A / 82S181B / 82S181C
Re: 21MX proms (per request
On 2015-Sep-08, at 2:39 PM, Jay West wrote: > Sean wrote > -- > The median listing price for them on eBay for a 29B with pack seems to be > around $3-400 which IMO is a little steep for a 30+ year old PROM programmer. > -- > Nope. There is a very good reason why they still command such a price. Worth > every penny. > > I can't belittle a 30 year old piece of test equipment no more than I could a > similarly aged computer :) Alternatively, for the rare instance of need, burning fusible PROMs generally or often isn't very complex. When I needed to burn a replacement 74S387 (256*4) for a repair awhile ago, I hacked up a programmer on a breadboard, controlled by a program running on an RPi. The hardware was an LM317, 7805, 3 TTL ICs, 5 transistors, and a few R/C/D. Add 4 more transistors for 8-bits.
RE: 21MX proms (per request
Sean wrote -- The median listing price for them on eBay for a 29B with pack seems to be around $3-400 which IMO is a little steep for a 30+ year old PROM programmer. -- Nope. There is a very good reason why they still command such a price. Worth every penny. I can't belittle a 30 year old piece of test equipment no more than I could a similarly aged computer :) J
Re: 21MX proms (per request
The median listing price for them on eBay for a 29B with pack seems to be around $3-400 which IMO is a little steep for a 30+ year old PROM programmer. Hopefully your best offer successfully accepted was much lower! I think the part cost on the PROMs pales in comparison. For the cost of the 29B, you could design a replacement for the original PROM, have some boards fabricated, stuff them and you'd still be ahead a few hundred bucks ... starts to make sense at those kind of prices, imo. Best, Sean On Tue, Sep 8, 2015 at 3:14 PM, Marc Verdiell wrote: > >From: dwight > >If I were doing it. > >First you need to find out if it needs OC output. > >There are many flash parts in surface mount that can have the higher > speeds. > >Add some 74LVC245 to give bus drive needed, also surface mount. > >All on a little PC board. There would be a lot of wasted space in the > flash > but what the heck. > >Put an edge connector on the board to deal with programming. > >All will fit in a smaller space than the original part. > >Dwight > > That would be great engineering fun! But at less than $4 for the blanks, > using the old PROMs and the vintage programmer seems pretty > straightforward, > vintage correct, and low risk solution. Miraculously, my best offer got > accepted on ebay, so semi-affordable vintage clunky Data I/O 29B Programmer > and plenty of blanks are being shipped to me :-). I count collecting > vintage > tools for servicing your vintage machine as part of the fun too... > Marc > > >
RE: 21MX proms (per request
>From: dwight >If I were doing it. >First you need to find out if it needs OC output. >There are many flash parts in surface mount that can have the higher speeds. >Add some 74LVC245 to give bus drive needed, also surface mount. >All on a little PC board. There would be a lot of wasted space in the flash but what the heck. >Put an edge connector on the board to deal with programming. >All will fit in a smaller space than the original part. >Dwight That would be great engineering fun! But at less than $4 for the blanks, using the old PROMs and the vintage programmer seems pretty straightforward, vintage correct, and low risk solution. Miraculously, my best offer got accepted on ebay, so semi-affordable vintage clunky Data I/O 29B Programmer and plenty of blanks are being shipped to me :-). I count collecting vintage tools for servicing your vintage machine as part of the fun too... Marc
Re: 21MX proms (per request)
On 09/07/2015 12:47 PM, Sean Caron wrote: But I do think there's merit in Alexandre's general argument that one could theoretically emulate the older bipolar PROMs with some mix of modern components ... and the programmable device would be (a) more easily obtainable than the old bipolar PROMs and (b) programmable with inexpensive, contemporary USB device programmers which are definitely big positives. Most likely, one could use a parallel modern EPROM that is as fast as the old bipolar PROM. Of course, the pinout would be totally different, probably in a larger size package with way more pins. This one is 256K and 70 ns access time. http://www.digikey.com/product-detail/en/AT28HC256-70JU/AT28HC256-70JU-ND/2050794 If you REALLY need it fast, Winbond has a 45 ns EPROM, but not in stock at Digi-Key. That's their W27C512-45Z Jon
Re: 21MX proms (per request)
I still do. And I'm even looking for an apple parker vector rollerball pen :) :) :) Em 08/09/2015 02:58, "j...@cimmeri.com" escreveu: > On 9/8/2015 12:28 AM, Marc Verdiell wrote: > >> Thanks for the answers everyone, I am writing everything down... >> Marc >> >> >> >> > Nice to hear that people are still *writing* things down... > > - J. >
Re: 21MX proms (per request)
On 9/8/2015 12:28 AM, Marc Verdiell wrote: Thanks for the answers everyone, I am writing everything down... Marc Nice to hear that people are still *writing* things down... - J.
RE: RE: 21MX proms (per request)
Thanks for the answers everyone, I am writing everything down... Marc
RE: 21MX proms (per request)
If I were doing it. First you need to find out if it needs OC output. There are many flash parts in surface mount that can have the higher speeds. Add some 74LVC245 to give bus drive needed, also surface mount. All on a little PC board. There would be a lot of wasted space in the flash but what the heck. Put an edge connector on the board to deal with programming. All will fit in a smaller space than the original part. Dwight > From: jw...@classiccmp.org > To: cctalk@classiccmp.org > Subject: RE: 21MX proms (per request) > Date: Mon, 7 Sep 2015 17:20:48 -0500 > > Sean wrote > - > But I do think there's merit in Alexandre's general argument that one could > theoretically emulate the older bipolar PROMs with some mix of modern > components ... and the programmable device would be (a) more easily > obtainable than the old bipolar PROMs and (b) programmable with inexpensive, > contemporary USB device programmers which are definitely big positives. > - > I agree... and have suggestions. Prior art exists, I have seen the arcade > crew use adapters to modify the pins of newer devices to be compatible. > > For loader roms, there are about 10 official images from HP. Plus, most users > (myself for sure) would want around 2 images that are user-created. The > system board supports 4 roms, selectable by front panel. The issue with the > solution the arcade crew has done - the adapters make the new memory devices > too tall to allow clearance above. In chassis after a certain date code there > is a cutout to access the rom sockets without removing the system board. In > those, the clearance issue is the bottom of the memory controller. In prior > revs, the issue is the metal work not providing clearance. I'm not saying a > solution can't be found, but whoever develops such a device needs to be aware > of the clearance issues particularly on the older rev machines. The only > thing I can think of that is likely to have proper clearance is a board that > has pins going to each 4 rom sockets, and the replacement memories are placed > under the board - not on top of it - carefully avoiding existing chips on the > system board. Regardless... whoever designs such a board needs to have a 21MX > in front of them to assure clearances. Also, I'd have to check, but the > precise spacing between the rom sockets may well be different between the M > and E versions. All that being said, it would be nice if the board supported > say 12 images, any 4 of which could be selected as active. > > Now, here's a better take on the problem design a card that goes into a > memory slot. Most all machines have many empty memory slots even when full of > memory. Then a ribbon cable could go down to a paddle board that plugs into > the 4 rom sockets. The board in the memory slot could get power straight from > the backplane. The ribbon/paddleboard relieves the clearance problem. Extra > points if this board also houses 1mw of ram and connects to the memory > controller as usual. Even better points if the board replaces the memory > controller and provides both 1mw ram plus loader roms :> > > For microcode, you'd sure have to find a way to get past the speed issue. > Since the 21MX's take microcode on the cpu board, or a FAB board, or a FEM > board (and the "fab" is very different on the 21MX/M)... you've got a lot of > choices. My bet - the most functional approach is to ignore trying to deal > with microcode prom replacement on the cpu and fab boards. Instead, provide a > single "new" "FEM" board that presents 24 bit wide memory modules of > appropriate speed. Basically, this becomes a WCS board - with modern memory > devices. There's a pretty large number of microcode options that could get > stuffed into such a device. The only down side - FEM boards take an I/O slot, > and one HP OS in particular will have an issue where I/O slots are > pre-allocated and not configurable at sysgen time. Extra points if the board > can also include devices that everyone always puts in - namely a TBG and > HSterm/BACI. Not sure how one could handle the select code logic in one slot, > would probably need paddleboards. But my advice - solve the speed issue first > ;) > > J > > > >
RE: 21MX proms (per request)
Sean wrote - But I do think there's merit in Alexandre's general argument that one could theoretically emulate the older bipolar PROMs with some mix of modern components ... and the programmable device would be (a) more easily obtainable than the old bipolar PROMs and (b) programmable with inexpensive, contemporary USB device programmers which are definitely big positives. - I agree... and have suggestions. Prior art exists, I have seen the arcade crew use adapters to modify the pins of newer devices to be compatible. For loader roms, there are about 10 official images from HP. Plus, most users (myself for sure) would want around 2 images that are user-created. The system board supports 4 roms, selectable by front panel. The issue with the solution the arcade crew has done - the adapters make the new memory devices too tall to allow clearance above. In chassis after a certain date code there is a cutout to access the rom sockets without removing the system board. In those, the clearance issue is the bottom of the memory controller. In prior revs, the issue is the metal work not providing clearance. I'm not saying a solution can't be found, but whoever develops such a device needs to be aware of the clearance issues particularly on the older rev machines. The only thing I can think of that is likely to have proper clearance is a board that has pins going to each 4 rom sockets, and the replacement memories are placed under the board - not on top of it - carefully avoiding existing chips on the system board. Regardless... whoever designs such a board needs to have a 21MX in front of them to assure clearances. Also, I'd have to check, but the precise spacing between the rom sockets may well be different between the M and E versions. All that being said, it would be nice if the board supported say 12 images, any 4 of which could be selected as active. Now, here's a better take on the problem design a card that goes into a memory slot. Most all machines have many empty memory slots even when full of memory. Then a ribbon cable could go down to a paddle board that plugs into the 4 rom sockets. The board in the memory slot could get power straight from the backplane. The ribbon/paddleboard relieves the clearance problem. Extra points if this board also houses 1mw of ram and connects to the memory controller as usual. Even better points if the board replaces the memory controller and provides both 1mw ram plus loader roms :> For microcode, you'd sure have to find a way to get past the speed issue. Since the 21MX's take microcode on the cpu board, or a FAB board, or a FEM board (and the "fab" is very different on the 21MX/M)... you've got a lot of choices. My bet - the most functional approach is to ignore trying to deal with microcode prom replacement on the cpu and fab boards. Instead, provide a single "new" "FEM" board that presents 24 bit wide memory modules of appropriate speed. Basically, this becomes a WCS board - with modern memory devices. There's a pretty large number of microcode options that could get stuffed into such a device. The only down side - FEM boards take an I/O slot, and one HP OS in particular will have an issue where I/O slots are pre-allocated and not configurable at sysgen time. Extra points if the board can also include devices that everyone always puts in - namely a TBG and HSterm/BACI. Not sure how one could handle the select code logic in one slot, would probably need paddleboards. But my advice - solve the speed issue first ;) J
Re: 21MX proms (per request)
On 9/7/15 8:34 AM, Alexandre Souza wrote: sometimes you gotta use flash devices that are WAY faster than common EPROMs... and sometimes that won't work, because the hold time of fast devices is too short.
Re: 21MX proms (per request)
But I do think there's merit in Alexandre's general argument that one could theoretically emulate the older bipolar PROMs with some mix of modern components ... and the programmable device would be (a) more easily obtainable than the old bipolar PROMs and (b) programmable with inexpensive, contemporary USB device programmers which are definitely big positives. Best, Sean On Mon, Sep 7, 2015 at 1:24 PM, Al Kossow wrote: > > > On 9/7/15 8:34 AM, Alexandre Souza wrote: > >> sometimes you gotta use flash >> devices that are WAY faster than common EPROMs... >> >> > and sometimes that won't work, because the hold time of fast > devices is too short. > >
Re: 21MX proms (per request)
As I said in the original post I wrote, sometimes you gotta use flash devices that are WAY faster than common EPROMs... 2015-09-07 12:32 GMT-03:00 John Robertson : > On 09/06/2015 2:00 PM, Alexandre Souza wrote: > >> Jay, no one is pin compatible, I always make adapters. But at least I make >> it work :D >> >> 2015-09-06 16:00 GMT-03:00 Jay West : >> >> Alexander wrote... >>> - >>> Intersting to note: many times i have used eproms in place of these >>> proms. >>> Usually, flash parts are faster, so better suited to the task. >>> - >>> >>> Loader roms: >>> You may be able to get by with that on loader roms. I've never found >>> eproms that were functional & pin compatible. What ones did you use for >>> the >>> 1K variety? >>> >>> Microcode: >>> I doubt seriously the eproms would be stable for microcode. HP specs 5ns >>> speed parts for the microcode; what eproms work and can hit those >>> speeds? I >>> suspect this is one of those "might seem to work" but is a really bad >>> idea. >>> >>> J >>> >>> >>> >>> As Jay points out, it is the access speed required by the device you are > substituting the EPROM for a ROM/PROM that counts. In some cases the 100 to > 400ns access speed of EPROMs won't matter (clock of under 1mHz for 400ns > 2716s to around 4mHz for 100ns EPROMs), but if you are running 10mHz or > faster reads then I suspect you will have problems unless you find faster > devices than EPROMs for your substitute ROM/PROM... > > John :-#)# > > -- > John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 > Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, VideoGames) > www.flippers.com > "Old pinballers never die, they just flip out" > >
Re: 21MX proms (per request)
On 09/06/2015 2:00 PM, Alexandre Souza wrote: Jay, no one is pin compatible, I always make adapters. But at least I make it work :D 2015-09-06 16:00 GMT-03:00 Jay West : Alexander wrote... - Intersting to note: many times i have used eproms in place of these proms. Usually, flash parts are faster, so better suited to the task. - Loader roms: You may be able to get by with that on loader roms. I've never found eproms that were functional & pin compatible. What ones did you use for the 1K variety? Microcode: I doubt seriously the eproms would be stable for microcode. HP specs 5ns speed parts for the microcode; what eproms work and can hit those speeds? I suspect this is one of those "might seem to work" but is a really bad idea. J As Jay points out, it is the access speed required by the device you are substituting the EPROM for a ROM/PROM that counts. In some cases the 100 to 400ns access speed of EPROMs won't matter (clock of under 1mHz for 400ns 2716s to around 4mHz for 100ns EPROMs), but if you are running 10mHz or faster reads then I suspect you will have problems unless you find faster devices than EPROMs for your substitute ROM/PROM... John :-#)# -- John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, VideoGames) www.flippers.com "Old pinballers never die, they just flip out"
Re: 21MX proms (per request)
On Sunday, September 6, 2015 at 13:41, Jay West wrote: > Here's a non-exhaustive but useful list of compatible parts for each: > > [...] > > 4K parts > Signetics N82S141 > Harris 7641 > MMI 6341 Some additional part numbers: - AMD Am27S31 - National DM87S474 > 8K parts > Signetics N82S181 > Harris 7681 > MMI 6381 Also: - AMD Am27S181 - National DM87S181 -- Dave
Re: 21MX proms (per request)
Jay, no one is pin compatible, I always make adapters. But at least I make it work :D 2015-09-06 16:00 GMT-03:00 Jay West : > Alexander wrote... > - > Intersting to note: many times i have used eproms in place of these proms. > Usually, flash parts are faster, so better suited to the task. > - > > Loader roms: > You may be able to get by with that on loader roms. I've never found > eproms that were functional & pin compatible. What ones did you use for the > 1K variety? > > Microcode: > I doubt seriously the eproms would be stable for microcode. HP specs 5ns > speed parts for the microcode; what eproms work and can hit those speeds? I > suspect this is one of those "might seem to work" but is a really bad idea. > > J > > >
Re: 21MX proms (per request)
On Sun, 6 Sep 2015, Jay West wrote: Here's a non-exhaustive but useful list of compatible parts for each: 4K parts Signetics N82S141 Harris 7641 MMI 6341 You can add National 74S474 to this group. I've tried it, and they work. Mike Loewen mloe...@cpumagic.scol.pa.us Old Technology http://q7.neurotica.com/Oldtech/
RE: 21MX proms (per request)
Glen wrote The loader PROMs are 256x4 while the firmware PROMs are either 512x8 or 1024x8. The firmware has some interesting code to unpack the 256x4 loader PROMs into 64x16 format in memory, and patch in the I/O select code while it is doing it. The same 1K parts are used interchangeably for loader roms or microcode on the FAB. They are the same chip regardless of if they contain loader code or microcode. J
RE: 21MX proms (per request)
Alexander wrote... - Intersting to note: many times i have used eproms in place of these proms. Usually, flash parts are faster, so better suited to the task. - Loader roms: You may be able to get by with that on loader roms. I've never found eproms that were functional & pin compatible. What ones did you use for the 1K variety? Microcode: I doubt seriously the eproms would be stable for microcode. HP specs 5ns speed parts for the microcode; what eproms work and can hit those speeds? I suspect this is one of those "might seem to work" but is a really bad idea. J
Re: 21MX proms (per request)
On Sun, Sep 6, 2015 at 11:41 AM, Jay West wrote: > Several people asked, here's the scoop: > > The common proms for HP 21MX M/E/F are 1K, 4K, and 8K. > > 1K are used for either loader roms on the cpu board or microcode on the FAB > 4K are used for microcode on the FAB or FEM > 8K are used for microcode on the FEM > The loader PROMs are 256x4 while the firmware PROMs are either 512x8 or 1024x8. The firmware has some interesting code to unpack the 256x4 loader PROMs into 64x16 format in memory, and patch in the I/O select code while it is doing it. I programmed at least one loader PROM using a BP Micro programmer. I forget exactly which PROM part I used. I probably have a very small number of blank PROMs left. I forget what loader PROM I swapped out and which one I swapped in. Sometime I'll have to fire up the system and dump the loaders PROMs into memory and check which ones I currently have installed, and make some notes so I don't have to wonder again later. -Glen
Re: 21MX proms (per request)
Intersting to note: many times i have used eproms in place of these proms. Usually, flash parts are faster, so better suited to the task. Em 06/09/2015 15:42, "Jay West" escreveu: > Several people asked, here's the scoop: > > The common proms for HP 21MX M/E/F are 1K, 4K, and 8K. > > 1K are used for either loader roms on the cpu board or microcode on the FAB > 4K are used for microcode on the FAB or FEM > 8K are used for microcode on the FEM > > The manuals you'll want to print and keep handy: > HP 12992 Loader Roms Installation Manual, 12992-90001 (April '86) > HP 1000 M/E/F-series Firmware Installation and Reference Manual, > 12791-90001 > (September, '83) > I believe these are both on bitsavers. They are "must have" manuals. > > These are all bipolar proms, and most modern prom programmers will not be > able to program them. I use a Data I/O 29B (with Unipak 2B), and it can > program all these parts. Those programmers appear on ebay from time to time > at around roughly $400. > > The blank proms are not terribly easy to find these days. Ebay has them > occasionally, but your best bet is sites that cater to arcade machine > repair. > > Here's a non-exhaustive but useful list of compatible parts for each: > > 1K parts > MMI 6301 > Harris 7611 > Signetics N82S129 > National 74S287 > TI 24S10 > AMD 27S21 > Fujitsu 7114 (possibly 7052 as well, need to verify that) > > 4K parts > Signetics N82S141 > Harris 7641 > MMI 6341 > > 8K parts > Signetics N82S181 > Harris 7681 > MMI 6381 > > >
21MX proms (per request)
Several people asked, here's the scoop: The common proms for HP 21MX M/E/F are 1K, 4K, and 8K. 1K are used for either loader roms on the cpu board or microcode on the FAB 4K are used for microcode on the FAB or FEM 8K are used for microcode on the FEM The manuals you'll want to print and keep handy: HP 12992 Loader Roms Installation Manual, 12992-90001 (April '86) HP 1000 M/E/F-series Firmware Installation and Reference Manual, 12791-90001 (September, '83) I believe these are both on bitsavers. They are "must have" manuals. These are all bipolar proms, and most modern prom programmers will not be able to program them. I use a Data I/O 29B (with Unipak 2B), and it can program all these parts. Those programmers appear on ebay from time to time at around roughly $400. The blank proms are not terribly easy to find these days. Ebay has them occasionally, but your best bet is sites that cater to arcade machine repair. Here's a non-exhaustive but useful list of compatible parts for each: 1K parts MMI 6301 Harris 7611 Signetics N82S129 National 74S287 TI 24S10 AMD 27S21 Fujitsu 7114 (possibly 7052 as well, need to verify that) 4K parts Signetics N82S141 Harris 7641 MMI 6341 8K parts Signetics N82S181 Harris 7681 MMI 6381
