Galivan - Cosmo Police Repair Log

Kaizen088

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Galivan - Cosmo Police Bootleg

I picked this up in a bunch of random untested boards and set it up on the test bench.





There's no schematic available that I could find, the pinouts and dips are available though.

When I powered it up most of the title screen is missing , there are just the moving stars.

In test mode there is no text and when a game is coined up and played there is no score.

The rest of the game seems to play fine, all sounds good and no issues with the background and characters.

[tube]0ZAQKFu8O7g[/tube]

With no schematic and the game playing relatively fine I started at the ROMs.

I found all outputs on ROM [D] were stuck high, there was no difference on screen when the chip was pulled, the game played the same. Pins were cleaned and inspected and look good. The 74LS257 got a pulse when the game goes to tile screen but the inputs are mostly high.



I have made the determination that the ROM is bad buy can't confirm this until I have a progammer (won't be long).

I'll shelve it until then.

Kaizen0882017-04-14 05:54:35
 
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