Hi there!

I've got a Godzilla I'm attempting to update the roms on.

The rom files in the 2.0.5 IPDB archive are the following files:
GDZCPU.205
GZDSPA.200
GDZU37.100
GDZU21.100
GDZU36.100
GDZU17.100
Gdzu7.100

Assumptions: I only need to burn the GDZCPU.205 and GZDSPA.200 since the game already has all 1.00 roms for sound, etc. (u37,u21,u36,u17 and u7 are all 1.00 already)

I burned two roms onto TI 27C040-10 chips: The GDZCPU.205 and the GZDSPA2.00 and replaced the CPU rom and the display rom. The game didn't boot. I swapped the CPU rom back for the 1.0 CPU rom, and the game booted fine on the old CPU and new display rom, displaying the display rom version as 2.00 at boot. This leads me to believe my burner is working correctly and I've got some clue as to what I'm doing. (I've done several pinball roms in the past with no issue). So i put the CPU rom back in the burner and confirmed it matched the file it was programmed with, and then tried a second and third 27c040. I get the same result each time. No boot. I've since tried using a file from a different source (First IPDB, then Internet Archive of Stern's old code page) and get the same result. No boot. Swap the 1.00 rom back in and it boots fine. I've been sure to verify the orientation of the chip, verified no missing or bent pins, and have the chip centered in the socket.

I'm using an EMP20 programmer on an old XP box.

What am I missing?

Thanks!

Greg