Problem:

• Game does not work. Screen has a bunch of legible static tiles.

Troubleshooting/diagnosis steps:

Watch the video walkthrough and explaination of this fix

• Fluke bus test OK
• Ram short 0x4000 - 0x43FF BTS 0x0F @ 4001 different BTS errors all in the low bits
• Ram short 0x4400 - 0x47FF OK
• Ram short 0x4c00 - 0x4fff - ok
• Lets replace the RAM that controls the low 4 bitgs of 0x4000 - 0x43FF
• Looks like 2114 @ 4H - just to verify clipped power pins and did retest
• Replaced RAM and now ram short works
• Game works!