Thomas Jentzsch Posted March 19, 2017 Share Posted March 19, 2017 Correction: EEPROMs Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted March 19, 2017 Share Posted March 19, 2017 You are telling me, that the Thwocker proto, that was found, uses an EEPROM? I thought only a couple of the CopyCarts used an EEPROM. I know Yoko and Universal were real EPROM's, but I think the Vidco uses an EEPROM. Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted March 19, 2017 Share Posted March 19, 2017 No, but EEPROMs where used during development. And later copied onto EPROMs. Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted March 19, 2017 Share Posted March 19, 2017 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.? Quote Link to comment Share on other sites More sharing options...
Thomas Jentzsch Posted March 19, 2017 Share Posted March 19, 2017 So, what's your theory? Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted March 19, 2017 Share Posted March 19, 2017 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. Quote Link to comment Share on other sites More sharing options...
Tempest Posted June 12, 2019 Author Share Posted June 12, 2019 Just thought I'd bump this and see if anyone has taken a closer look at Thwocker in the past two or so years. Quote Link to comment Share on other sites More sharing options...
Swami Posted August 22, 2019 Share Posted August 22, 2019 I still don't see the fixed one posted. Is it still getting pulled for some reason? It's like the Voldemort of hacks. Quote Link to comment Share on other sites More sharing options...
Supergun Posted August 22, 2019 Share Posted August 22, 2019 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. 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) Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted August 22, 2019 Share Posted August 22, 2019 Yes, OTP EPROM's are the same as UV erasable EPROM's, the chip select line needs to be inverted the same way. Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted August 23, 2019 Share Posted August 23, 2019 I just realized, I didn't answer your other question, those boards are testy about EPROM speed, I had some EPROM's not work on those, when making Activision repros. Quote Link to comment Share on other sites More sharing options...
Supergun Posted September 3, 2019 Share Posted September 3, 2019 Well I have tried all of the following EPROMs and none of these work: intel D2764 intel FD2764 NEC D2764D Fujitsu MBM2764 AMD AM2764 SEEQ Do you recall which ones specifically you actually had success with? Quote Link to comment Share on other sites More sharing options...
CPUWIZ Posted September 3, 2019 Share Posted September 3, 2019 Try CMOS, E.G. 27C64. 1 Quote Link to comment Share on other sites More sharing options...
MegaManFan Posted September 3, 2019 Share Posted September 3, 2019 On 8/21/2019 at 10:53 PM, Swami said: I still don't see the fixed one posted. Is it still getting pulled for some reason? It's like the Voldemort of hacks. Having noticed this thread I'm interested in trying it myself. Quote Link to comment Share on other sites More sharing options...
Swami Posted September 5, 2019 Share Posted September 5, 2019 On 9/3/2019 at 6:56 PM, MegaManFan said: Having noticed this thread I'm interested in trying it myself. F8 suffix:https://atariage.com/forums/topic/295416-thwocker-versions/?do=findComment&comment=4338678 bin suffix: 1 Quote Link to comment Share on other sites More sharing options...
Supergun Posted May 17, 2020 Share Posted May 17, 2020 On 9/3/2019 at 7:31 PM, CPUWIZ said: Try CMOS, E.G. 27C64. Just following up here. I finally got some CMOS style EPROMs. I tried the ST Micro M27c64A and it didn’t work either. No dice. Quote Link to comment Share on other sites More sharing options...
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