PCB Repair Logs World Rally
World Rally
PCB Image | Reserved |
---|---|
Pin Out | Reserved |
Repairer: VectorGlow
Forum Thread: World Rally PCB Repair
Symptom: Some colours wrong, for example car sprite colours and the hand at the start of a race. Also the test card colours in test mode
Cure: Bad outputs on pins 12 and 13 of the 74LS298 at location G3
Symptom: Some text a bit mangled
Cure: Broken pin 7 on 27C4001 at location I11
Symptom: Couldn’t adjust sound volume correctly
Cure: A 5K volume pot had been used instead of the correct 4.7K
Symptom: On power up, giving: RAM ERROR AT 00203FFE (sometimes the last three alphanumerics varied)
Cure: Bad OKI MSM6295 at location C6
Symptom: Sound a mess
Cure: Bad OKI MSM6295 at location C6
Symptom: Starting speech ‘3 – 2 – 1 Go’ kept repeating
Cure: Pin 34 (A16) loose on OKI MSM6295 at location C6
Symptom: 1 pixel high horizontal black line across the whole display on every other pixel line. Also colours a bit off.
Cure: Bad output on pin 15 of the 74LS298 at location I3
Repairer: truxpin
Forum Thread: World Rally PCB Repair
World Rally board 1
This board seams to have had a hard life a quick look over revealed eprom C23 missing and the corner broken off the PCB through the mounting hole near I22.
Started by cleaning up the damaged board corner and repairing a damaged track then burn a new eprom for C23.
Powering up showed some success well at least booted. Test screen showed test pattern but text was messed up and not readable in game. Background ok, text and car messed up. Sound consisted of just beeps and squawks.
More visual inspection revealed more damaged track this time between D17 and F17. Repairing these fixed the text and car graphics. Now for the sound suspecting the OKI Chip and or mask rom. I pulled the rom it verified ok.
The board was shelved at this point to get some data on the OKI chip and have a think about it. This payed off when I realised it was playing the correct sound track, just too fast with most of the notes missing. This ead to replacing the faulty 1Mhz ceramic resonator at C7.
Board now working.
Not a bad game lots of fun and even works 2 player with joysticks in a cocktail.