GQ-4x4: Can't read CPS2 EPROMs

Pretty Amy

Host for Orochi
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Sep 15, 2013
Posts
755
Total EPROM noob here.

I want to phoenix my CPS2 games. I'm already talking to razoola, but I need to be able to read the existing roms to verify them before I can purchase the phoenix roms. I'm using a GQ-4x4 and a ADP-054 adapter that I bought new off of Amazon. I can't tell if something is wrong with the programmer/adapter or if I'm just being stupid (highly probable). The device in the software is set to "27C4096" but it just reads 0xFF for every byte. The game hasn't been suicided yet and is working just fine so I know the roms are in good shape.

Here are some pics of the programmer/adapter:

U6iJVyH.jpg


Pe6cArm.jpg


  • Adapter is in the bottom pins of the programmer (i.e. top 2 rows are empty on programmer)
  • Jumpers are in the default location (tried the other options to no effect too)
  • Tried both with and without an external power supply plugged in
  • Tried placing the EPROM in the socket a few different ways (to the left, right, and center)

Any help is appreciated.
 
Last edited:

mainman

CPS2 Person.,
Joined
Mar 26, 2001
Posts
3,351
If the software supports device ID turn it off than try to read with 27c4002 and 27c240
 

Pretty Amy

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lol, reading it as 27c4002 works! Thanks for the help. What's the reason those other chip IDs would work instead of the 27C4096?
 

mainman

CPS2 Person.,
Joined
Mar 26, 2001
Posts
3,351
The 27c4096, 27c240 and 27c4002 are interchangeable, the only variance is the device ID. The issue you are having with not being able to program under the correct part number is solely the fault of the manufacturers software.

On a related note the 27c400 and 27c4100 are the inverse equivalent of the previously mentioned chips, this info is handy when reading and programing cps1 mask roms.
 
Last edited:

Pretty Amy

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Sep 15, 2013
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Thanks again for the help, mainmain! :buttrock:

Relieved to get this thing working.
 
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