Author Topic: Programmer for TMS2516  (Read 10252 times)

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Offline Eheran

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Programmer for TMS2516
« on: June 23, 2016, 07:21:03 pm »
Vpp is 25V and there are numerous reports of problems with these due to a voltagedrop in the programmer.
So there are these Willem devices in lots of variations that claim to have Vpp 25V and some even list the TMS2516. However... considering how some say that the powersupply cant handle the current... I have seem some Willem like this one claiming to have a better voltage stability.

I need a good Programmer... or at least one that will work with that chip. Ideas are welcome.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #1 on: June 23, 2016, 08:04:40 pm »
You could avoid the whole problem by using 2816 EEPROMs instead.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #2 on: June 23, 2016, 09:55:05 pm »
I have to read them first and AFAIR there were the same problems with droping Vcc  :-//
So lets say i get a Minipro TL866 - can it read them without a problem? How hard is it to replace TMS2516 with 2816 EEPROM? Do i only have to worry about the pinout?
 

Offline blacksheeplogic

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Re: Programmer for TMS2516
« Reply #3 on: June 23, 2016, 10:13:45 pm »
I need a good Programmer... or at least one that will work with that chip. Ideas are welcome.

The Conitec GALEP programmers support these but they are quite expensive programmers unless you find them used.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #4 on: June 23, 2016, 10:16:22 pm »
I have to read them first and AFAIR there were the same problems with droping Vcc  :-//

That doesn't make sense, read is 5V only.

Quote
So lets say i get a Minipro TL866 - can it read them without a problem? How hard is it to replace TMS2516 with 2816 EEPROM? Do i only have to worry about the pinout?
Yes, of course a TL866 can read TMS2516s (which are more commonly known as 2716s BTW).

TMS2516 and 2816 are pin compatible for reading.

You want to get X2816s or other 5V only parts.
 

Offline blacksheeplogic

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Re: Programmer for TMS2516
« Reply #5 on: June 23, 2016, 10:36:03 pm »
TMS2516 and 2816 are pin compatible for reading.

The TMS2516 was TI's version of the Intel 2716.

Yes, of course a TL866 can read TMS2516s (which are more commonly known as 2716s BTW).

I don't know for sure as I don't own this particular programmer. You would think all of the programmers should easily handle these old chips, but not all do and those that do usually have a external supply. I would suggest asking on one of the 8-bit forums specifically about this programmer to make sure first.
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #6 on: June 23, 2016, 10:51:36 pm »
Are you sure the 2516 is fully compatible and pinequal to the 2716?
I know that for instance the 2532 and 2732 are not pincompatible.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #7 on: June 23, 2016, 11:00:08 pm »
Yes, of course a TL866 can read TMS2516s (which are more commonly known as 2716s BTW).

I don't know for sure as I don't own this particular programmer. You would think all of the programmers should easily handle these old chips, but not all do and those that do usually have a external supply. I would suggest asking on one of the 8-bit forums specifically about this programmer to make sure first.
We are only talking about reading, not programming.
Why would an external supply be required when the part only needs 5V for reading?

Are you sure the 2516 is fully compatible and pinequal to the 2716?
Yes and no.
TMS2516 = Intel and generic 2716
TMS2716 = different
« Last Edit: June 23, 2016, 11:03:50 pm by edavid »
 

Offline blacksheeplogic

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Re: Programmer for TMS2516
« Reply #8 on: June 24, 2016, 10:09:39 am »
Are you sure the 2516 is fully compatible and pinequal to the 2716?
I know that for instance the 2532 and 2732 are not pincompatible.

Yes.
 

Offline blacksheeplogic

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Re: Programmer for TMS2516
« Reply #9 on: June 24, 2016, 10:24:27 am »
Yes, of course a TL866 can read TMS2516s (which are more commonly known as 2716s BTW).

I don't know for sure as I don't own this particular programmer. You would think all of the programmers should easily handle these old chips, but not all do and those that do usually have a external supply. I would suggest asking on one of the 8-bit forums specifically about this programmer to make sure first.
We are only talking about reading, not programming.
Why would an external supply be required when the part only needs 5V for reading?

The TMS2516 was not popular and a lot of programmers don't actually support it. As far as reading vrs writing, the original question was regarding the 25V programming voltage, Secondly, I would not buy a programmer to use with a TMS2516 just because it should work. That particular chip has a reputation for being a "should work" mistake.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #10 on: June 24, 2016, 02:31:02 pm »
The TMS2516 was not popular and a lot of programmers don't actually support it.
It was popular enough, it was a second source for the Intel 2716 (so it was supported by every programmer that supported the 2716).  It was the original TMS2716 that was unpopular.

Quote
As far as reading vrs writing, the original question was regarding the 25V programming voltage, Secondly, I would not buy a programmer to use with a TMS2516 just because it should work. That particular chip has a reputation for being a "should work" mistake.
Sometimes it helps to read the other posts in the thread  :-//

Quote
So lets say i get a Minipro TL866 - can it read them without a problem?
« Last Edit: June 24, 2016, 02:34:32 pm by edavid »
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #11 on: June 24, 2016, 03:35:34 pm »
So im going with a TL866 programmer and XLS2816AP-250 2kx8 EEPROM like this one, correct?
They seem to be pin-compatible with the TMS2516 except for pin 18 and 20 (CE and OE).
 

Online edavid

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Re: Programmer for TMS2516
« Reply #12 on: June 24, 2016, 06:44:19 pm »
So im going with a TL866 programmer and XLS2816AP-250 2kx8 EEPROM like this one, correct?
They seem to be pin-compatible with the TMS2516 except for pin 18 and 20 (CE and OE).

That seems fine.

Why do you think CE and OE are not compatible with the TMS2516?


 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #13 on: June 25, 2016, 08:56:49 am »
Well Pin 18 CE is Chip Enable on the 2816 vs. Power Down/Program on the TMS2561.
Pin 20 OE is Output Enable vs. Chip Select?
I was asuming that is not the same, but i gues it can be the same just "in other words"  :popcorn:
 

Online edavid

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Re: Programmer for TMS2516
« Reply #14 on: June 25, 2016, 11:18:13 pm »
Well Pin 18 CE is Chip Enable on the 2816 vs. Power Down/Program on the TMS2561.
Pin 20 OE is Output Enable vs. Chip Select?
I was asuming that is not the same, but i gues it can be the same just "in other words"  :popcorn:

If you look at the pin descriptions, they are compatible for reading.  Since you won't be trying to write in circuit, there is no problem.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #15 on: June 30, 2016, 03:45:56 pm »
I just tryed to read all 3 EPROMs. Either i failed to do it right or they are all 100% empty, passing blank checks...  :palm:
Any Ideas? Is it possible that they really lost 100% data?
Did i do something wrong?
Im using the Minipro programmer and selected MBM2764 for the MBM 2764-25 and tryed several different 2516-types on the TSM2516.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #16 on: June 30, 2016, 04:07:19 pm »
Any Ideas? Is it possible that they really lost 100% data?
Not really.

Quote
Did i do something wrong?
Are you sure you inserted them correctly in the socket?
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #17 on: June 30, 2016, 04:14:41 pm »
 |O
Ouch. Never mind.  :-DD
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #18 on: June 30, 2016, 05:41:35 pm »
This could have killed them  :o
If I knew you had no experience I would have kept my mouth.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #19 on: June 30, 2016, 08:12:14 pm »
So how does anyone get experience...?
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #20 on: June 30, 2016, 08:20:38 pm »
By first using some eprom that is not vital to the repair of your device, reading the eprom programmers manual and asking questions here before doing something you never done before?
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #21 on: June 30, 2016, 08:50:50 pm »
I tested with a new EEPROM first, of course. That showed up as empty, as to be expected. Now why would the device tell me anything when it cant possibly read the chip? That lead me to believe everything was alright and i went on, "reading" the EPROMs.

Anyway. The EPROMs either already lost data (i read them with 4,5-5,5V and they always verified okay) or there is some other defect in the machine. Maybe the manufacturer sends me the original Data, but i doubt it. One of them contained the different languages, so that was fairly easy to check as the words were okay. But the other two are not simply ascii. How could i translate the Hex to something readable as the original code or whatever? Or any other ideas how i could check the data?
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #22 on: June 30, 2016, 09:08:33 pm »
No you probably can not check it. If you are lucky and the device firmware writers clever there is a checksum on the code that will be checked on power up. So you save the code, write it to an (e)prom put them inthe device and see if it still works.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #23 on: June 30, 2016, 09:16:03 pm »
It doesnt work. Im doing all this because of it not working in the first place  ;)
But since i can see the languagedata loaded from the new EEPROM it has to be alright in terms of copying the old ROMs and accepting the new EEPROMs.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #24 on: June 30, 2016, 09:52:33 pm »
This is very confusing.  What problem were you trying to solve by copying the EPROMs?
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #25 on: June 30, 2016, 10:09:57 pm »
Those are TSM2516 EPROMs from almost 30 years ago, see here for more details:
https://www.eevblog.com/forum/repair/mettler-fp80-broken/
 

Online edavid

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Re: Programmer for TMS2516
« Reply #26 on: June 30, 2016, 11:50:07 pm »
Sorry, I didn't see the other thread.

I'm not sure why you thought the EPROMs were the cause of the original problem.  If properly programmed, EPROMs are very reliable.

Do you see any difference in behavior with the EPROMs vs the copies you made?
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #27 on: July 01, 2016, 04:15:11 am »
It was suggested that they lose data.
No difference with the error, still mostly "A/D conversion error (overflow)".
 

Offline stj

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Re: Programmer for TMS2516
« Reply #28 on: July 03, 2016, 02:39:04 am »
why dont you just buy an old professional programmer from the 80's off ebay??

i have a micromaster1000 that does every eprom from 2716 to 27c040 AND pals & gals & bproms & 8bit mcu's.
much simpler than buying usb junk.
 

Offline helius

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Re: Programmer for TMS2516
« Reply #29 on: July 03, 2016, 02:58:36 am »
why dont you just buy an old professional programmer from the 80's off ebay??

i have a micromaster1000 that does every eprom from 2716 to 27c040 AND pals & gals & bproms & 8bit mcu's.
much simpler than buying usb junk.
I tend to agree, but that also requires that you have a working computer with a parallel port, unless you find one of the higher-end programmers with serial comms (which were primarily products of Data I/O or Stag).
 

Offline stj

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Re: Programmer for TMS2516
« Reply #30 on: July 04, 2016, 07:14:53 am »
you just reminded me that i also have an ELAN wih serial interface. :)
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #31 on: July 04, 2016, 08:02:29 am »
why dont you just buy an old professional programmer from the 80's off ebay??
That is something I did and cost still a lot of money (four times more than a new chinese 866 programmer) but the problem is that you only do that if you have more old equipment you want to service or that is your interest.
For the OP this is his only apparatus that was broken and he wanted a cheap and fast way to do it, then a new programmer that supports the chip is the best advice IMO, otherwise you could get stuck in more problems (old Windows version 95 or XP, old pc with par.port etc. etc.) than necessary for the job at hand.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #32 on: July 04, 2016, 08:18:39 am »
Correct. Just replacing them with EEPROMs costs a lot less and 0 problems are to be expected.
Buying a old programmer could cause who knows how many problems.

And there is another point: Nobody told me about another programmer that can do the job. Even if it would be much better... i need to know about it first  ;)
 

Offline helius

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Re: Programmer for TMS2516
« Reply #33 on: July 04, 2016, 02:42:05 pm »
you just reminded me that i also have an ELAN wih serial interface. :)
Now there's a beauty, with support for 110 and 134.5 baud, and RCA COSMAC!
http://matthieu.benoit.free.fr/elan_E2A_editing_programmer.htm
 

Offline stj

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Re: Programmer for TMS2516
« Reply #34 on: July 04, 2016, 07:56:37 pm »
mine is a 5000 gang programmer, not an E2A

anyway, if the guy just needs one set of devices for one project/repair, it would be simpler to just ask on the forum for someone in the same country to program the devices for them.  :-+
 

Offline janoc

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Re: Programmer for TMS2516
« Reply #35 on: July 04, 2016, 10:47:03 pm »
So im going with a TL866 programmer and XLS2816AP-250 2kx8 EEPROM like this one, correct?
They seem to be pin-compatible with the TMS2516 except for pin 18 and 20 (CE and OE).

I have checked the sw for my TL866 and it certainly lists generic Intel 2716 as supported, also the TMS2716 variant. At least reading should certainly be possible, but I have no way to test as I don't have any of these chips on hand.

The software allows selecting the programming voltage up to 21V. Not sure whether that is good enough or not for your chip - it doesn't appear to be able to do 25V.
 

Offline stj

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Re: Programmer for TMS2516
« Reply #36 on: July 05, 2016, 05:39:22 am »
another option is to find some 27c16's

pretty rare, but cmos & pin compatable with 12.5v vpp
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #37 on: July 05, 2016, 10:46:14 am »
Well, the new EEPROMs work just fine. But i dont know wether the data in the old EPROMs is corrupted form dataloss. The company doesnt seem to send me that data, making that a a dead end for me... i can try to troubleshoot the hardware* all i want, if the ROMs are corrupt im not getting anywhere.
So how likely is a dataloss after 30 years?


OT: Too bad i cant programm... i would build a Arduino based version to manage the data. So absorption/transmission of light in 3 points and 2 Pt100 sensors + powering a heating element, transmission gets higher when the substance melts -> meltingpoint.
*I have no clue where to start. How would i detect a defective A/D converter? They all get some input and give some sort of output... but is it correct? I dont know.
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #38 on: July 05, 2016, 11:21:42 am »
So how likely is a dataloss after 30 years?
Are you sure it is from 1986? My guess is that device is probably older than 30 years, the 2532's were already available in 1979.
The problem with eproms is that there was no data retention tests and guarantees back then. So from my own experience I have seen 2708s still ok from 1977 but also failed 2732's from devices from the 80's (game machines) So it all depends on lifetime, temperature (hot device environment), leakage of the unique silicon die etc. etc. In theory only one capacitor that has a worse leakage then the rest could cause the software to fail the checksum.
So I personally advise people to backup and copy (reburn) their eproms from before the 1990's within 20 years.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #39 on: July 05, 2016, 11:37:42 am »
Lots of other chips are from 1985 and some 1984. The EPROMs themselfe are 49. week 1984.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #40 on: July 05, 2016, 03:17:00 pm »
So how likely is a dataloss after 30 years?
Highly unlikely.  EPROMs in ceramic packages are usually the most reliable parts in the product.

Quote
*I have no clue where to start. How would i detect a defective A/D converter? They all get some input and give some sort of output... but is it correct? I dont know.
It's more likely to be the circuitry around the ADC.
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #41 on: July 05, 2016, 04:14:51 pm »
Aha... so the original information about EPROMs losing data and causing the trouble might be false?

What should i look at around the ADC? How would i see any anomalys? Sorry for these questions, my understanding of electronics is simply not high enough.
 

Offline helius

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Re: Programmer for TMS2516
« Reply #42 on: July 05, 2016, 05:07:02 pm »
Aha... so the original information about EPROMs losing data and causing the trouble might be false?

The structure of an EPROM is similar to SLC flash, with data stored by charge trapped on a floating gate. Over time, charge carriers tunnel out of the gate making the stored data weaker. Data retention is not infinite.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #43 on: July 05, 2016, 05:07:25 pm »
Aha... so the original information about EPROMs losing data and causing the trouble might be false?
I think so.

Quote
What should i look at around the ADC? How would i see any anomalys? Sorry for these questions, my understanding of electronics is simply not high enough.
Do you have the ADC datasheet?
 

Online edavid

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Re: Programmer for TMS2516
« Reply #44 on: July 05, 2016, 05:08:33 pm »
The structure of an EPROM is similar to SLC flash, with data stored by charge trapped on a floating gate. Over time, charge carriers tunnel out of the gate making the stored data weaker. Data retention is not infinite.

Of course not, but under normal conditions it is > 100 years.

 

Online wraper

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Re: Programmer for TMS2516
« Reply #45 on: July 05, 2016, 05:15:58 pm »
The structure of an EPROM is similar to SLC flash, with data stored by charge trapped on a floating gate. Over time, charge carriers tunnel out of the gate making the stored data weaker. Data retention is not infinite.

Of course not, but under normal conditions it is > 100 years.
If you are lucky, that is according to accelerated tests, and not every type. Many have ~20 year spec. EPROM corruption is not very common but isn't rare either. Don't know about this particular type but some obsolete types of those times now start t loosing their data like plague.
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #46 on: July 05, 2016, 05:19:29 pm »
Of course not, but under normal conditions it is > 100 years.
I don't know your experience but I have encountered numerous eproms from end 70s begin 80s that failed.
Sometimes I could recover the original data by lowering the Vcc during reading.
100 years? Some new flash roms will not even survive that, don't forget that the silicon processes in the 70s were far less on quality and repeatability as they now are.
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #47 on: July 05, 2016, 05:20:56 pm »
That said, in this particular case the eproms seem to be ok. So the problem lies somewhere else.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #48 on: July 05, 2016, 05:41:38 pm »
The structure of an EPROM is similar to SLC flash, with data stored by charge trapped on a floating gate. Over time, charge carriers tunnel out of the gate making the stored data weaker. Data retention is not infinite.

Of course not, but under normal conditions it is > 100 years.
If you are lucky, that is according to accelerated tests, and not every type. Many have ~20 year spec. EPROM corruption is not very common but isn't rare either. Don't know about this particular type but some obsolete types of those times now start t loosing their data like plague.

Whatever, I have yet to see a retention failure in a 2716, even for the ones I programmed myself 30+ years ago, without being very careful.

It's a moot point, since OP's repair theory doesn't really hold up.  If the EPROMs were good, copying wouldn't help, and if they had retention errors, copying also wouldn't help  :-//  The only way it would have worked was if the EPROMs read OK in the programmer, but not in the system.  I don't believe OP did any fooling around with the supply voltage while reading.

100 years? Some new flash roms will not even survive that, don't forget that the silicon processes in the 70s were far less on quality and repeatability as they now are.
Quality problems mostly lead to random failures, rather than data retention errors.

Older parts were actually specified in a much more conservative way, especially the programming algorithms.  When you only have 16K cells, you don't have to worry much about programming time, so you can overprogram the hell out of it.

That said, in this particular case the eproms seem to be ok. So the problem lies somewhere else.
I don't see where there's any evidence one way or the other, but I don't see EPROM failure as especially likely.  If the error message points to the ADC, surely that's the first place to look.
« Last Edit: July 05, 2016, 05:46:36 pm by edavid »
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #49 on: July 05, 2016, 05:52:13 pm »
Older parts were actually specified in a much more conservative way, especially the programming algorithms.  When you only have 16K cells, you don't have to worry much about programming time, so you can overprogram the hell out of it.
True. Don't forget that these are eproms not mask roms , so they were actually designed to be erased and loose its charge , though due to uv radiation still there is not such a thing as a infinite isolation, there will always be some leakage. Also if the windows is not 100% shielded there is a chance on light leakage how minor even causing charge leakage.
Just google for vintage computer repair, pinball repair and video arcade games repair and you find many examples of the old eproms loosing their charge, still 40 years I think is extremely good and respectable and as you say a lot keep their charge over that period.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #50 on: July 05, 2016, 06:00:33 pm »
Just google for vintage computer repair, pinball repair and video arcade games repair and you find many examples of the old eproms loosing their charge, still 40 years I think is extremely good and respectable and as you say a lot keep their charge over that period.

Maybe the EPROMs on that type of board led a harder life than a set that were programmed once and then sealed inside a scale for 30 years.  It's hard to figure out how any significant UV would make it through the scale case and EPROM labels.
 

Offline Kjelt

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Re: Programmer for TMS2516
« Reply #51 on: July 05, 2016, 08:43:02 pm »
So what is your experience with these eproms and how many are we talking about?
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #52 on: July 05, 2016, 09:05:33 pm »
Quote
I don't believe OP did any fooling around with the supply voltage while reading.
I veryfied with 4.5V 5.0V and 5.5V Vcc. All identical.

Quote
Do you have the ADC datasheet?
So far i found one ADC, Datasheet down below. Maybe you find more ADC... here is the PCB.
 

Online edavid

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Re: Programmer for TMS2516
« Reply #53 on: July 05, 2016, 09:30:16 pm »
Interesting... did you look at the ADC input voltage?

[I mean pin 10]
« Last Edit: July 05, 2016, 10:33:13 pm by edavid »
 

Offline Eheran

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Re: Programmer for TMS2516
« Reply #54 on: July 05, 2016, 09:43:49 pm »
V+ is at 4,9V
V- is at -15V
 

Offline stj

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Re: Programmer for TMS2516
« Reply #55 on: July 06, 2016, 09:17:45 am »
if you read the eprom about 5 times and it gives the same checksum every time then it's probably good.
most eprom failures start with data being on the 0/1 freshhold so each read is a bit different.

professional programmers already do this, when you read, they do multiple reads and compare them - some also shift the voltage up and down in .5v steps.
 

Offline rsjsouza

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Re: Programmer for TMS2516
« Reply #56 on: September 20, 2019, 02:58:02 am »
Sorry for the necroposting, but I noticed that the original question was not answered.

Yesterday and today I tried to program a few blank TMS2516JDL devices using my TL866CS, thoroughly erasing them with UV eraser between attempts. I can attest this programmer cannot reliably program these devices, as they use 25V programming voltage. 

I used the following parameters:
TL866CS SW version 6.85
Vpp = 21.0V
Vcc verify = 5.0V
Vdd Write = 5.0V
Pulse delay = 1000µs

I hope this helps someone in the future.
Vbe - vídeo blog eletrônico http://videos.vbeletronico.com

Oh, the "whys" of the datasheets... The information is there not to be an axiomatic truth, but instead each speck of data must be slowly inhaled while carefully performing a deep search inside oneself to find the true metaphysical sense...
 


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