PAC-MAN and other PROMs

[obitus1990]

Is there any somewhat modern substitute for the PROMs used on this and other boards? I don't have a programmer capable of programming them. Even an adapter board that adapts surface mounted flash chips would be fine.

 

[steph]

I can provide pretty much any type of prom you would need.
( original drop-in replacements )

Adapter boards are a little clunky, and would probably cost just as much, if not more
than the proms they would be replacing.

PM me with what you need.

Cheers,
Steph
www.Hobbyroms.com

 

[DogP]

I've built/used adapters to adapt W27C512s and AT27C256Rs, and they work fine... but like @steph said, they're kinda chunky, and really, probably not any cheaper. While I have a programmer that can program bipolar PROMs, I don't keep many in stock, so the biggest advantage for me is being able to quickly burn/test with what I've got on-hand, then eventually go back and replace with a real PROM.

@SNESNESCUBE64 posted a bunch of adapter gerbers to his github here: https://github.com/SNESNESCUBE64/27C256_to_PROM_Adapter (I think I came across someone else's gerbers as well), and others have sold adapters over the years.

DogP

 

[andrewb]

Adapters aren't as clunky if you remove any original sockets, and just solder the adapter board low to the PCB. Then they look almost like any other ROM.

I've used brzezicki's adapters that he used to sell on his site. Them all you need is a GQ-4X and W27C512 EEPROMs, which are cheap.

 

[obitus1990]

I've built/used adapters to adapt W27C512s and AT27C256Rs, and they work fine... but like @steph said, they're kinda chunky, and really, probably not any cheaper. While I have a programmer that can program bipolar PROMs, I don't keep many in stock, so the biggest advantage for me is being able to quickly burn/test with what I've got on-hand, then eventually go back and replace with a real PROM.

@SNESNESCUBE64 posted a bunch of adapter gerbers to his github here: https://github.com/SNESNESCUBE64/27C256_to_PROM_Adapter (I think I came across someone else's gerbers as well), and others have sold adapters over the years.

DogP

I went and took a look at that repository... the adapters there don't include 7603 (the PROM at 7F) or the 1M5623 (4A PROM). Are there any known adapter boards for these types of PROMs to use the same OTP PROMs @SNESNESCUBE64 is using with his adapter, OR are the parts designations (7604 and 5623) just another manufacturer's part number for the same pROMs his adapters were designed for?


Nevermind...answered my own question: https://www.mikesarcade.com/cgi-bin/spies.cgi?action=url&type=info&page=PromRef.txt

 

[DogP]

There's a good cross reference here: https://www.mikesarcade.com/cgi-bin/spies.cgi?action=url&type=info&page=PromRef.txt .

From that:
7603 is equivalent to 82s123
5623 is equivalent to 82s129

DogP

 

[SNESNESCUBE64]

So I designed these to be used with the AT27C256R-45 OTP eproms. However, those have been out of stock for quite some time now. They should be able to be used with the W27C512, it's just that you would have to write on the second half since it would have the A15 would be tied high since it is normally Vpp on a 27c256.

I really should add jumpers to use the W27C512-45s since atmel/microchip hates me and won't restock the their OTP eproms.