Problem:

• Game does not work
• Getting "ROM error #7"

Troubleshooting/dianosis steps:

1. Replaced CPU Socket @ 2C and 1D, found bad custom 08xx @ 1D
2. Game boots but having graphics issues
3. Sprites are messed up and background seems to flash with backgrounds that are coming up soon
4. Found previous work at 1F, replaced 20 pin socket @ 1F, no change
5. Swapped 82S153 with another one from another board, same problem occurs
6. Pulling 5m and 5n, running without them, looks like one of those is probably the issue. (These are sprite RAMS), Found one of these were bad, replaced, which fixed the sprite issues.
7. Still have the background issues
8. After tons of going down rabbit holes, which I won't bother writing up here I found that 1F was bad after, apparently the replacement was bad too, de soldered one from another board and use, and not it works fine
9. Game works!

Problem:

• Game works but video issues

Troubleshooting/dianosis steps:

1. Custom 04xx @ 2N was plugged in incorrectly
2. Bad 6116s either 2r 2p or 2s, swapped one at a time till I found it was 2R, replaced
3. This one has sprite issues too, they are being drawn wrong.
4. 6Mhz at 3n #11 and 4S #1 seem odd problem steps from 74LS368 @ 5B Pulled 5B, there’s a signal on output line #5 which should be floating without 5B! Think I found a bridged trace, that fixed that problem!
6. After burning in testing board failed. game would boot but after self test the game would sit frozen at the splash screen with "FF" credits
7. found custom @ 6H, replaced, but now sprite "explostion animations" are wrong when you shoot flying objects
8. Pushed on the ERPOMS 4r-4m, things changed. Removed sockets, they were bad, and replaced sockets
9. That solved the problem
10. Noticed while play testing that the explosion sounds were missing, that shold be the custom 54xx @ 6A
11. Replaced, that fixed the problem
12. Game works!