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

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

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

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

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

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

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 -

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

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

> 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-remember

Re: 21MX proms (per request

- Original Message - From: "tony duell" <a...@p850ug1.demon.co.uk> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk@classiccmp.org> Sent: Thursday, September 10, 2015 2:29 PM Subject: RE: 21MX proms (per request Your right, I didn't say

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 &

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

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

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

> > 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 :

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

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

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 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

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

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

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

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

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

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,

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

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

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

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...

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.

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

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

RE: 21MX proms (per request)

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 >

RE: RE: 21MX proms (per request)

Thanks for the answers everyone, I am writing everything down... Marc

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: 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,

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)

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

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

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

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,

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

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.

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