Fastchip in eprom?

[+Larry]

I would like to replace the 800 (not XL) math rom with a Newell Fastchip in eprom.  I have read that the math rom is a 2316 pinout.  Has anyone done this?  I think it would require a 27 or 25 series eprom with an adapter?  This has been discussed before, but I can't find any threads that actually say anyone has been successful.

[BillC]

1 hour ago, Larry said:

I would like to replace the 800 (not XL) math rom with a Newell Fastchip in eprom.  I have read that the math rom is a 2316 pinout.  Has anyone done this?  I think it would require a 27 or 25 series eprom with an adapter?  This has been discussed before, but I can't find any threads that actually say anyone has been successful.

I believe the 2516 has the same pinout as the 2316, except that chip selects can be different, the 2516 can be difficult to source and can't be programmed by many modern devices.

 

There are adapters that allow 27XX chips to be substituted for a 2316/2332/2364, below is a link to the 23XX adapter by Retro Innovations:

http://www.go4retro.com/products/23xx-adapter/

Edited December 7, 2022 by BillC

[+Larry]

Thanks.  I have a couple of their 23xx adapters.  IIRC they have two different ones.(?)  I used at least one to replace XL/XE Basic with an eprom.  But I'm hopeful that someone has successfully done this with the Math Rom.

[BillC]

3 hours ago, Larry said:

Thanks.  I have a couple of their 23xx adapters.  IIRC they have two different ones.(?)  I used at least one to replace XL/XE Basic with an eprom.  But I'm hopeful that someone has successfully done this with the Math Rom.

I don't personally know of anyone who has done it with the Math ROM, but it's just a matter of rerouting signals due to different pinouts. Incompatible chip select signals would need to be changed as well, EPROM chips selects are fixed while those for mask ROMs can be customized.

 

Some Atari 600XL PCB manufacturers built adaptors into their 600XL PCB versions(allows using 2764 EPROM instead of 2364 mask ROM for internal BASIC) and all 1050 PCB manufacturers did similar(allows using 2732 EPROM instead of 2732 EPROM for firmware).

Edited December 8, 2022 by BillC