Mask Rom identification list ?

Black IcE

Earl's Long Lost Brother,
Has a list ever been compiled of mask rom types and the equivalent chips that can be read by eprom programmers ? I am getting into doing more board repairs but am still learning about the different types of chips and the best way to verify them.

My current project is a Tatsujin board that I am trying to resurrect. I've verified the program roms and (I think) a sound rom, but I haven't been able to figure out the correct chip type to read the graphics mask roms (LH2309BJ). I tried doing some online searching, and someone said they were able to read them as a 27C1000 or a 27C301. I am under the impression that I will need to make a 27C301 to 27C010 adapter to verify the chips, but the mask rom is 28 pins and a 27C301 is 32 pins. Any input would be appreciated. I am using a GQ-4x programmer. Thanks.


Bub & Bob's Bubble Buddy,
On my outzone board a few of the maskroms have been replaced with 27c010s. It looks like they left pins 32, 31, 1, 2 out of the socket, hooked up pins 32, 31, 30, 1 together with wire and pin 2 went to a jumper on the board JP9...which I'm guessing is ground/ a way for it to recognize the new eproms?
Last edited:


Trollbox Trade Federation,
If you cant read 27c301 / 27c1000 then you need to make an adapter to read as 27010. The 28 pin mask rom is missing /P, Vpp and /OE.

If you wire up the remaining pins to the 27010 standard it should read fine.