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jwestfall69 / neogeo-diag-bios

Disassembly of smkdan's Neo Geo Diagnostics BIOS with added features
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VRAM 2K DEAD OUTPUT (UPPER) #22

Closed Icelvlan88 closed 3 years ago

Icelvlan88 commented 3 years ago

Hello,

Do you know what this error means? Cannot find anything outside on it.

VRAM 2K DEAD OUTPUT (UPPER)

Rolel commented 3 years ago

It means the RAM seems to be outputting nothing when attempting to read it. Most commons causes are dead RAM (very likely for 2k RAM) or the RAM /OE trace may be cut.

Icelvlan88 commented 3 years ago

I swapped them and check pin 20. Was hoping there might be another reason. I’m not getting any sprites just text. Hmm my OE is grounded. Where is supposed to go back to? These are CXK5814P-35L. Here is more information

VRAM DATA (0000) ADDRESS: 008000 ACTUAL: FF00 EXPECTED: 0000

Icelvlan88 commented 3 years ago

Fixed problem.