Caius

Pang repair log #1

Sep 102014

Tired of all the (bad engineered) Pang bootlegs I have had in the past, I bought this mint not working original one:

As you know Pang is one of the CAPCOM Pre-CPS games that use a battery to supply power to a RAM that holds a decryption table. This table is the key to decrypting the encrypted program stored in the board’s ROMs.When the battery runs out, this table goes away and the program code can no longer be decrypted so the board stops working.And, since the board is manifactured in 1989 and mid lifespan of a battery is 3-4 years, nowadays most of the Pang boards suffer from this issue.

Powered up my board, I got this static brown screen, clear symptom that also my board ‘suicided’:

For some years it’s possible to revive this (and others) board thanks to the work of Tim from Arcadecollecting.Infact I followed the instructions on his site (keep only attention to use the proper ROM set specific for your game revision):

https://www.arcadecollecting.com/dead/pre-cps.html

and I could add a full working original Pang PCB to my collection:

Pang (World revision) PAL dump added

PAL Updates Comments Off

Sep 102014

Today I ‘desuicided’ an original CAPCOM Pang (World revision) PCB and I took the opportunity to dump the only PAL present.Device was originally a PAL16L8 marked ‘POKER’ (go figure why…).Dump is tested and working in a GAL16V8 targeting device.

Master of Weapon PAL dumps added

PAL Updates Comments Off

Sep 072014

Here are the dumps from an original Taito Master of Weapon PCB.All dumps were obtained from three unsecured devices (PAL16L8) and then converted to GAL16V8 fuse map.All of them are tested and working.Repair log of this PCB will follow soon.

Jigoku Meguri (Bonze Adventure) repair log #1

PCB Repair Logs, Repair Logs Comments Off

Aug 282014

I got this Bonze Adventure (actually, it ended to be Jigoku Meguri, the japanese version) PCB as gift from my friend Silvio:

Board was in decent state but it was missing the YM3016F DAC and the TC0100SCN tilemap generator :

so I used a Drift Out faulty PCB as donor for these two ICs.

Besides, some pads of the TC0100SCN ASIC were missing and the RGB module TC0070RGB fell off in my hands once I touched it.I rebuilt missing pads using some AWG30 wire and I exposed the TC0070RGB pins using my Dremel in order to solder new legs:

RGB module doesn’t use a standard 2.54mm pitch but 1.77mm so I used an half of a 64 pin S-DIP socket for its installation on PCB:

All was set and ready for powering on the PCB.Once done, I got a solid black screen but all activity on 68000 adreess/data bus seemed fine.So I’ve started to think about a video RAM failure and I piggybacked a 62256 RAM over the one @IC4 which had some data lines stuck HIGH, this was the result:

so I desoldered it and tested out of circuit resulting as showed:

But, though I replaced this RAM, I got the same error.So I remembered that my friend Silvio told me a lot of Bonze Adventure had both the tile RAMs bad so I decided to desolder also the other one 62256 RAM @IC5 and he was right, it was really bad!

Fitted another good one and :

I could enjoy this weird game!Thank you again , Silvio, for donating me this PCB and for your precious advices! 🙂

Hellfire repair log #1

PCB Repair Logs, Repair Logs Comments Off

Aug 232014

As usually I got this Hellfire PCB from ebay quite cheap.The game itself is an old school horizontal shoot ’em up manifactured from Toaplan.At first sight the PCB was clean except for some corrosion in the bottom right corner.

Once powered it on I was greeted by this screen:

Looking at MAME memory map I found no trace of this specific offset which is at end of 68000 addressable memory (this CPU can address up to 16 MBytes).So I decide to start over again and give a deeper look at the PCB, in particular to the mentioned corroded area.I found that some pins of the ASIC marked “FCU BG1” were lifted.According to MAME source this chip handle the tiles generation and this would (partially, since device is not mapped in this memory region) explains the RAM error.

I tried a reflow but pins were so much corroded that I could not get a good soldering so I opted for a transplant with another same ASIC from a scrap Hellfire PCB but before doing this I cleaned the area from oxide and corrosion exposing the ASIC pads very well.This was the result:

Confident I powered the board on and :

100% fixed!

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