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No, but EEPROMs where used during development. And later copied onto EPROMs.

 

The official devkits from Atari, that I own, use RAM. Never seen a lab-loaner with an EEPROM either. I wonder what Activision used, did anyone ever ask any of the regular Activision guys that show up for CGE etc.?

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So, what's your theory?

 

I am not sure how that could happen, unless they used a programmer over and over and only loaded parts of memory on top of each other, without clearing the buffer first.

 

Dumb really, EPROM's program faster if parts of your ROM are $FF, those cells are ignored. One of the reasons I designed the 4K board, that only uses 28pin EPROM's (27128 & 27256), not only do they program faster in the first place, but the rest of the EPROM is just zipped through. Overall still a big win over programming a 2532 or 2732. Tons of homebrews from the AA store use these boards. Oh yeah, and the 28pin EPROM's are actually cheaper and easier to get than 4K EPROM's. ;)

 

I think the only company that did this on the 2600 was Froggo, they used 27C64 OTP EPROM's for their 4K games. Not all, mind you, the label variations from Asia, do not use EPROM's.

 

Way off topic, I know. :lol:

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On 3/19/2017 at 4:10 PM, CPUWIZ said:

 

I am not sure how that could happen, unless they used a programmer over and over and only loaded parts of memory on top of each other, without clearing the buffer first.

 

Dumb really, EPROM's program faster if parts of your ROM are $FF, those cells are ignored. One of the reasons I designed the 4K board, that only uses 28pin EPROM's (27128 & 27256), not only do they program faster in the first place, but the rest of the EPROM is just zipped through. Overall still a big win over programming a 2532 or 2732. Tons of homebrews from the AA store use these boards. Oh yeah, and the 28pin EPROM's are actually cheaper and easier to get than 4K EPROM's. ;)

 

I think the only company that did this on the 2600 was Froggo, they used 27C64 OTP EPROM's for their 4K games. Not all, mind you, the label variations from Asia, do not use EPROM's.

 

Way off topic, I know. :lol:

Would you happen to know why those Froggo carts that did utilize these 27c64 One Time Programmable EPROM’s require a hex inverter?

 

(I know I touched on this subject once before with you)

 

The reason why I’m asking is because if normally, a hex inverter is used to allow an EPROM to be used as a substitute in a mask rom setting, then wouldn’t the fact that a hex inverter is used with these 27c64 OTP roms indicate that their pin outs are wired like an eprom? But yet, when a regular 27c64 eprom is placed there, it does not function.

 

Or in more plain words, is there any eprom that you know of that is a pin compatible drop in replacement for this 27c64 OTP chip?

 

(even if using a different size such as a 2732 or a 27c128)

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