ZN-2 Question

[Hackcell]

Does anybody know if it's possible to recreate/replace the PAL in a ZN2 B board?

I have this Rival Schools B board that had 2 EPROMs damaged and only displayed a color partern. After replacing the faulty EPROMs, I get a CanNotFrinProgramRom. All EPROMs are OK (even the mask and I've tried reburning the Country PROM even in a new EPROM. So, my only guess (unless somebody else has experienced the same and know what's going on), it may be the CAT702 PAL is damaged.

 

[Hammy]

Double check rom #5

The cat 702 is the security chip, can be bypassed with a bios board:

View: https://www.youtube.com/watch?v=-MAu8I2pnBM


If the CPS2-B custom is dead it's game over.

 

[Hackcell]

Didn't work. Same B930 error. Isn't it the CPS B custom the same found in CPS-2 boards?

 

[Hammy]

Swap the romboard with a known good before going any further.
Otherwise the bios board is recommended to bypass the CAT chip.