Caius

Hard Puncher repair log

Nov 082017

Received this quite rare Hard Puncher (on Konami Twin16 hardware) for repair:

PCB failed all the time the self-test showing a bad device @10G on CPU board and then resetted, this in an endless loop:

The involved device is a Mitsubishi M5M5165 (8K x 8-bit static RAM) compatible with 6264 :

Its data bus showed no activity:

The chip failed the out-of-circuit test each time in a different address location:

With a good RAM the board successfully booted into game:

But speeches were missing, here is a comparison with a MAME recording:

I quickly pinpointed this fault in a missing 640KHz ceramic resonator, this is for generating clock to the uPD7759 ADPCM speech synthesizer IC.I took a spare from a dead Sega System16B motherboard:

Job done.

Super Burger Time repair log

PCB Repair Logs 1 Response »

Nov 012017

Got this Super Burger Time PCB (by Data East) for a repair:

Board played fine except for the fact the BLUE color was totally missing hence the yellowish screen:

Palette RAMs are two 2K x 8-bit devices, both were Sony CXK5814 (6116 compatible) which are well known to be unreliable:

Probing them revealed that the one @9K had all data lines stuck low while address were happily toggling (on left of the below picture)

The IC was most likely bad so I removed it:

The out-of-circuit confirmed it:

Replacing it fixed the board completely.

Super Burger Time PAL dumps converted and tested.Pang 3 and Knight of Valour Super Heroes PAL dumps added

PAL Updates Comments Off

Nov 012017

Another PALs update today.

I have converted to GAL16V8 fuse map the Super Burger Time PAL dumps we had from Luiskiko time ago, they all works fine when tested.

‘cpsystem3’ sent in dump (successfully tested by himself) of the PLD present on a Knight of Valour Super Heroes PGM cartridge, thanks to him.

Lastly, I dumped the PLD @1F from what appears to be a well made reproduction of Pang 3 B-BOARD

Equations of PAL are different from original board since bootleg use eight 4Mbit GFX ROMs instead of the two 16Mbit ones of genuine boardl.All other PALs are identical to original.Dump is untested for now since board is not working.

Big PAL dumps update

PAL Updates Comments Off

Oct 292017

Today we have a massive update.Dumps came from the following PCBs:

Athena bootleg

Porchy dumped the PALs from a copy board and successfully tested dumps back on board.Corrado Tomaselli confirmed dumps are working also on the original PCB.Devices were all unsecured (two PAL16L8 and one PAL20L8) and they have been reversed into GAL devices (for the 24 pin one both GAL20V8 and GAL22V10 replacement available).Thanks again to both them.

Cyberball (prototype with serial #0002)

Dumps were provided by ‘coolmod’ on Dumping Union list from an early revision/protoype of board.Devices were all unsecured PAL16L8.We mark them as “assumed working” since we have no means of testing GAL replacements.Thanks to him.

Locked ‘n Loaded

256KB binary PAL dumps provided by Smitdogg on Dumping Union from a faulty board.I reversed them into GAL fuse map which we mark as ‘untested’ until testing on a working PCB will be done.Thanks to him.

Gokidetor (a mechanical wack a mole type game by Taito)

Dumps provided by Smitdogg on Dumping Union, devices were all unsecured.We mark them as “assumed working” for now.Thanks to him.

Bobble Bobble (bootleg of Bubble Bobble)

I dumped and reversed into GALs the three PALs from this one layer bootleg.All dumps matches the two layer version (dumped by Porchy some time ago) except for one which has slightly different equations.

Tecmo World Cup ’94

Board has six PALs but I was able to dump and reverse into GAL only the one @U64.

Pipe Dream

I dumped the PLDs from a dead board.Out of four devices present one was registered so not dumpable.Dumps are untested for now until we can test them on a working board.

CPS1 ‘DASH’ A-BOARD repair log

PCB Repair Logs 2 Responses »

Oct 252017

Received this faulty Capcom CPS1 A-BOARD, actually the ‘DASH’ revision with a 12MHz oscillator in place of 10MHz one:

Board played with good graphics but sound samples were completely wrong and randomly played, here’s a video made with a Captain Commando B-BOARD/C-BOARD:

PCM samples are played by an OKI ‘MSM6295’ IC which addresses two 1Mbit devices (located on B-BOARD) and reads back their data.Judging from flux residuals the IC was previously reworked on this board as well as other components of audio circuit:

For first I tested all traces to/from it, all was OK.So, most likely, the IC was bad, no wonder since it’s a prone to failure part.I removed it:

Cleaned the PCB from flux and installed the spare:

Time to test:

Board fixed.End of job.

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