Anything special about programming 27512 eproms ?

[dave_m]

Just checked my device list for the Unipak 2B and it requires V27 firmware and adapter 351B086 for the AMD 27C512, It's the Unipak 2 that requires V23 firmware to program that chip.

My information that V23 was OK for the Unipak2B came from the Data I/O 1991 Wall Chart and the AMD 27C512 was listed in bold type which indicated a recent algorithm change. If your information came from a later source then it implies that the algorithm kept changing. There must be something 'special' about the AMD part...

 

[mc68010]

My information that V23 was OK for the Unipak2B came from the Data I/O 1991 Wall Chart and the AMD 27C512 was listed in bold type which indicated a recent algorithm change. If your information came from a later source then it implies that the algorithm kept changing. There must be something 'special' about the AMD part...

Maybe I should try and find a non-AMD 512 and try it on my burner. I am not really sure why all I have is AMD parts. I pulled them off all sorts of different gear and AMD is all I've found so far. They must have been pretty common.

 

[Malc]

In the early 1990's AMD did a die shrink on the 27C512 eproms and there was an algorithm change on the Unipak 2B to reflect the changes, also the FPO code was changed. There's a post on this on the Yahoo Data I/O Programmer's group.

If you can find a very early 1990 AMD 27c512 chip it should work with V23, What are the date codes of the chips you have ?.

My information that V23 was OK for the Unipak2B came from the Data I/O 1991 Wall Chart and the AMD 27C512 was listed in bold type which indicated a recent algorithm change. If your information came from a later source then it implies that the algorithm kept changing. There must be something 'special' about the AMD part...

 

[dave_m]

In the early 1990's AMD did a die shrink on the 27C512 eproms and there was an algorithm change on the Unipak 2B to reflect the changes, also the FPO code was changed. There's a post on this on the Yahoo Data I/O Programmer's group.

If you can find a very early 1990 AMD 27c512 chip it should work with V23, What are the date codes of the chips you have ?.

OK, that makes sense. The date code on the device seems a little cryptic: 918LA6Z. Probably 1991 part? Wow, Looking into the quartz window, the geometry of the matrix seems a lot finer than a 2764. I wish I had a microscope.
-Dave

Update: The date code for this EPROM is on the underside of the part: 8915 so it is a 1989 part and V23 would have worked (however I have V21). In the Data I/O forum, they mentioned trying code 0DA/0A4 and disabling the electronic ID check. The algorithm is probably a low yield one for this part, but might work. I'll give it a shot.

 

[Malc]

Worth a shot if you have a non AMD 512, I'm not familiar with the willem's but how old is it, try a AMD 512 a bit older than the willem, There was a change on the AMD 27C512 in the early 90's.

Maybe I should try and find a non-AMD 512 and try it on my burner.

 

[mc68010]

Worth a shot if you have a non AMD 512, I'm not familiar with the willem's but how old is it, try a AMD 512 a bit older than the willem, There was a change on the AMD 27C512 in the early 90's.

Here's an example of the Willhem burner. http://www.sivava.com/EPROM_Programmer_5.html As far as I can tell it was designed a few years ago by someone named Willhem and put out as opensource hardware for anyone to make or change. The Chinese produce a 100 different versions of the same thing under 100 different names. There are tons of different ones on ebay alone. The run about $30 - $50 and most get shipped directly from China. The quality varies greatly and often resistors and caps of the wrong value are installed from what I have read. There is no central source of software. I think there was only ever a beta version that the original people made that has been modified over the years for improvements made to the design. The latest version is still only version 0.98 .

Its a popular programmer for more modern devices like those found in cable boxes, consoles, and car computers. I don't think most owners care about the 27xxx stuff. If there was a bug in that portion it might go unnoticed and unfixed forever and nobody would care.

 

[Malc]

I remember looking at similar types a long time ago, Don't know if you have seen the forums at mcumall . com but they have a section for the "open source project willem programmer hardware" might be worth a look, hope you get it sorted soon.

Here's an example of the Willhem burner...