T O P I C R E V I E W |
oahu99 |
Posted - 03/22/2016 : 10:24:17 Hello, I am working on testing a few memory chips I pulled from an NES game. The two chips were a 32K and a 128K EPROM. I have the CRC32 for the chips so I know what should be on them. I was able to read the 32K chip because its pinout is identical to a 27c256, and the checksum matched. For the 128K eprom, its pin out is not identical to another existing eprom. I think I may need to create a custom device for it to read correctly. Can anybody give me a hand?
Here's the pinout of the mask rom, it's 128Kbytes ---_--- PRG A15 - |01 28| - +5V PRG A12 - |02 27| - PRG A14 PRG A7 - |03 26| - PRG A13 PRG A6 - |04 25| - PRG A8 PRG A5 - |05 24| - PRG A9 PRG A4 - |06 23| - PRG A11 PRG A3 - |07 22| - PRG A16 PRG A2 - |08 21| - PRG A10 PRG A1 - |09 20| - PRG /CE PRG A0 - |10 19| - PRG D7 PRG D0 - |11 18| - PRG D6 PRG D1 - |12 17| - PRG D5 PRG D2 - |13 16| - PRG D4 GND - |14 15| - PRG D3 ------- |
1 L A T E S T R E P L I E S (Newest First) |
ZLM |
Posted - 03/22/2016 : 11:52:01 It seems only A16 is difference. Your should be able to red the chip second half content twice.
You can disconnect the chip pin A16 and connect that pin to the pin just above the A15 of programmer IZF.
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