Pacland repair log#2

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Oct 282018
 

Received a pacland board for a repair which was stuck with a  0 2 0 error at boot.

Normally the middle digit means it’s an program rom error and infact the second prg rom @8D had no sticker  and I immediately checked it.

 

Romident showed it was a Pacland midway rom, but the other prg roms belonged to the japanes new version.

After burning the correct 2nd rom from the jap set I was welcomed with this screen which is the service one.

The dipswitches were all set OFF and after verifying they were working correctly I decided to change all the FUJITSU 74LS257 near them which had dead outputs infact.

In the end all the Fujistsu chips has been changed because faulty: @1L, 2L and 2J!

 

With good ones changed the game finally booted but the palette was very tinted and the sprites were corrupted:

 

Verifying the sprites roms 8,9,10 and 11 these were a mess of different revisions, so using a broken pacland I put the matching roms from the new japanese set

Still the sprites were corrupted and eventually I found a bad 74ls86 ( again Fujitsu) @10F

 

With good one installed I got finally good sprites but still the palette was tinted:

 

I proceeded on the colour prom section and found that the chip PL1-2 had some outputs dead

 

Using one from another Pacland board fixed the game 100%

 

 

 

Pacland repair log

 PCB Repair Logs  Comments Off on Pacland repair log
Nov 092017
 

Got this Pacland, Sidam version, in mint conditions  for a repair

The game had some color bitplanes of the sprites shifted to the left as you can see from this pic

The sprites are handled by CUS29 and there are two 2149 rams connected.

Piggybacking a good 2149 ram on top of the one @3T restored good colours

Testing it out of circuit confirmed it was bad

The game had no other faults and was 100% fixed