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Pretty Soldier Sailor Moon repair log

Jul 052015

Got this Pretty Soldier Sailor Moon PCB from my friend Ifog:

He told me that gameplay was fine but some of the audio/voice samples were missing or played wrongly.This was confirmed once I fired it up, here’s a brief audio recording:

As beginning of my troubleshooting, for first, I identified the audio digital circuitry:

As you can see from picture above, PCM samples data contained in the two MASK ROMs (40 and 42 pins) are read by two OKI MSM6295 PCM voice synthesis chips (while music is generated by a YM2151).So, I went to probe the MASK ROMs and found that the one @U47 had some address lines stuck as well as the control lines /CE and /OE.

Most of the address lines are directlty connected to the respective OKI MSM6295 chip so I replaced it but with no luck.Instead, I could trace the /CE and /OE lines back to a GAL16V8B @U28.Probing the outputs of this GAL revealed they were all stuck LOW.So. I tried to read it in my EPROM programmer which failed reporting an error:

I also read and disassembled it with my dedicated hardware, it was like empty :

/* Dedicated input pins */

pin 1 = I0; /* Unused input */
pin 2 = I1; /* Unused input */
pin 3 = I2; /* Unused input */
pin 4 = I3; /* Unused input */
pin 5 = I4; /* Unused input */
pin 6 = I5; /* Unused input */
pin 7 = I6; /* Unused input */
pin 8 = I7; /* Unused input */
pin 9 = I8; /* Unused input */
pin 11 = I9; /* Unused input */

/* Input and/or bidirectional pins */

pin 12 = B0; /* Unused input */
pin 13 = B1; /* Unused input */
pin 14 = B2; /* Unused input */
pin 15 = B3; /* Unused input */
pin 16 = B4; /* Unused input */
pin 17 = B5; /* Unused input */
pin 18 = B6; /* Unused input */
pin 19 = B7; /* Unused input */

This confirmed definitively that the device was bad.At this point the only possibility was taking a good GAL chip from another PCB or dumping and reproducing it.

Luckily my friend Ifog had a same board with a good GAL and he was able to provide me the binay dump which I took care of analysing and reversing it (see my latest PAL updates here).Once programmed a blank GAL16V8 device and fitted it on PCB, all the PCM samples were restored.Job done.

Pretty Soldier Sailor Moon PAL dumps added

PAL Updates Comments Off

Jul 042015

Today, during a repair (log will follow later) I created the replacements for the two remaining PLDs (two secured GAL16V8B) from a Banpresto Pretty Soldier Sailor Moon PCB.With these two dumps we have now a complete PLDs set of this PCB since the other three (PEEL18CV8 devices) have already been dumped and uploaded on our database though they remain untested.Thanks to Ifog for providing me binary dump of one of the two GALs.

X-Multiply (IREM M72 hardware) PAL dump added

PAL Updates Comments Off

Jul 042015

In the last days I dumped the specific PLD (a PAL16L8) from a X-Multiply PCB (IREM M72 hardware, PAL is on top board ‘M72-C-A’).Chip was kindly provided by my friend ‘robotype’ and dump has been tested as working from ‘cpsystem3’ in a GAL16V8 targeting device.Thanks to both.

Gaiapolis & Metamorphic Force repair log (a.k.a Konami ‘054573″ color DAC reworking)

PCB Repair Logs, Repair Logs Comments Off

Jun 302015

As every arcade fan/collector probably knows, Konami makes great things but… sometimes weird.Technically speaking every their board (starting from old ones like Gyruss to latest ones ) has its own hardware layout which involves the use of custom ASICs (Application Specific Integrated Circuit).These ICs are used to semplify the layout and prevent board bootleging.They can have most disparate shape and package and do various functions (sound, graphics, I/O and so on).In particular the Konami ones are really well made but often prone to failure.Some example of their customs :

The one I faced during this double repair log is the one marked ‘054573″ .It’s used on hardware of mid ’90s, it has SIL 15PIN package and it’s essentially a color DAC, it converts digital color signal into an analog one outputting it directly on JAMMA connector (so one IC is used for each RGB colors) :

Here is the IC ‘naked” , picture kindly provided by IronGiant:

It’s a quite fragile part, indeed while I was testing a Gaiapolis PCB, I switch it OFF/ON and I got this (picture on the right) :

Green color was suddenly missing.Once identifying the ‘054573’ DAC responsible of this color I compared with a logic probe its pins to the ones of the other two DACs and they had exactly the same activity except for PIN2 which is , indeed, the output connected to PIN12 solderside of the JAMMA edge.Observed with an analog scope confirmed the output was silent compared to an healthy one of a good DAC:

Replaced it and the green color was restored :

The second PCB, a Metamorphic Force one which also use this kind of DAC, was perfectly working but someone made an awful job on the solderside, “piggybacking” a good ‘054573’ DAC on the faulty one (the green color one also here) and fixing it with hot glue:

Since the eye wants its part, I decided to revert this orrible hack restoring the original status and testing successfully the board :

Konami does great but weird things always, remember! 🙂

Gyruss test/diagnostic rom update

General Comments Off

Jun 302015

16/03/2018

Minor fix.

Text references 8C instead of 19E when sub-cpu EPROM fails checksum.

Fixed output to reference 19E.

04/07/2015
Minor changes.
1.Holding down player 2 start during powerup will enter the diagnostic mode.
2.Some changes made to the presentation of the sprite viewer

30/6/2015
This update includes character and sprite test menu additions to the diagnostic mode. Useful for verifying bad tiles and sprites.
See roms section / downloads for update.

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