Spectral Vs. Generation (SVG) PGM Cart Repair

 PCB Repair Logs, Repair Logs  Comments Off on Spectral Vs. Generation (SVG) PGM Cart Repair
Sep 122024
 

In for repair was a Spectral Vs. Generation (SVG) cartridge for the Poly Game Master platform by IGS. It was booting up to a garbled screen.

SVG was a late release for the PGM platform, and it incorporates strong anti-piracy measures that IGS didn’t have in their earlier games. The cart has an ARM CPU with an embedded ROM that both decrypts encrypted assets and processes some of the logic for the game. The game has yet to be patched to operate without the ARM CPU, and the embedded ARM ROM hasn’t been fully dumped yet with this game. If the ARM CPU fails, that’s pretty much a project killer.

The owner of this cart also sent along a fully functional second SVG cart, and through cross-testing, I confirmed that the CHAR board of the faulty cart is fine while the CPU board is the culprit. I dumped the three EPROMs from the CPU board and while the dumps matched MAME, the good cart wouldn’t boot with the “V200 U30” EPROM installed from the faulty cart, so I programmed and installed a replacement 27C4096 EPROM for that part.

This still didn’t get the faulty cart booting so I moved on to reflowing the ARM CPU and confirming that the ARM was receiving a clock signal from the onboard crystal at U35. The cart still froze at bootup so I reached out for help on the Arcade Projects forums. On there, Fluffy helpfully suggested installing the three GAL chips from the functioning board into the faulty board – a dumb oversight on my part. 😀

Installing the GALs from the working cart got the faulty cart booting to an EXTERNAL RAM TEST ERROR screen.

Replacing the SRAM chip located at U38 resolved this error and now a new error appeared – SHARE RAM 1 TETS (sic) ERROR.

I replaced both the SRAM chips located at U37 and U38. This resolved that error and now the cart was booting up successfully!

I still needed replacement GALs though, and the GALs for this game hadn’t yet been dumped. I reached out to Apocalypse and he graciously offered to dump the GALs for me. I shipped him the carts, he dumped the GALs and the PLD files are now available at the PLD Archive.

Now that the original good GALs were installed back in the working cart, the final step was to program fresh GALs with Apocalypse’s PLD files and swap them into the faulty cart. The faulty cart booted up fine and passed a four hour burn in test. Repair complete!

Thunder & Lightning repair log

 PCB Repair Logs, Repair Logs  Comments Off on Thunder & Lightning repair log
Aug 152024
 

Got a Thunder & Lightning, a nice ball and paddle game from Seta on the bench today.

At first glance the board looked fine, but there was some worrying rusted pins on one LS close to the 68000 … not sure why, but other chips around weren’t affected.

I replaced the chip and patched the traces with some kynar wire.

When powered up, a working game displays a moving patchwork of tiles for a few seconds before displaying the title screen. In this board case, the tiles patchwork was displayed, but it kept rebooting just before displaying the title screen.

On this board, dipswitch 1 of the first bank puts the game in test mode. Doing so displays a color grid, and after pressing a button you get to the input test. The board worked flawlessly in test mode, meaning the main CPU worked enough to run it. But when pressing the reset button on the board, the following message started to show: “Address Error 2020E6”, before rebooting again …

Not knowing where this address pointed to, I looked into Mame to find the memory map of the game. And I found something very interesting : a PALCE is used as a protection device, using some address lines as inputs and computing a value that’s grabbed later by the CPU … if the value isn’t the one expected, a soft reset is done. That looks reaaally familiar !

Here’s the offending chip (TL-9) :

It was removed …

.. and replaced by a GALV16V8, using the file from the PLD archive. I added a support just in case.

And voilà !

Played a few levels to be sure nothing’s amiss, all is good !

Namco Rompers repair log

 PCB Repair Logs, Repair Logs  Comments Off on Namco Rompers repair log
Aug 032024
 

I’ve had this board in my collection for some years and I’ve made some repair work on before (replacing the cus120 on the CPU board, might put up a repair log on that as well).
I was going through my PCB collection and found that the game would not boot, there was only a black screen and not even the usual klonk sound as Namco System 1 games usually do.

Started with the basics, probed the Program ROMs with my logic probe and I did see some activity on the address and data buses.

Decided to dump the Program ROMs and verify them and they turned out to be ok.

So I started to probe the address and data buses again and found an address line (A2) that was stuck low.

Traced this line back to a 74LS244 at E10

74LS244 is a buffer and according to the Pac-Mania schematics, pin 14 is the output which has its input at pin 6 and there was activity there

This made me quite certain that the 74LS244 at E10 was bad.
But just to be certain, I removed all Program ROMs and the Custom key chip, so none of them would interfer.

And the fault was still there.
I quickly desoldered the 74LS244 and tested it with my tester as bad

I soldered a socket in its place and replaced the IC with a known good one and now the game booted up again

Nanao MS9-29 Arcade Chassis Capacitor List

 Capacitor Lists  Comments Off on Nanao MS9-29 Arcade Chassis Capacitor List
May 142024
 
Location Capacitance uF Voltage V NOTES
C102 1 50
C107 22 50
C201 47 50
C202 47 50
C203 47 50
C211 2.2 50
C212 2.2 50
C213 2.2 50
C220 470 35
C221 100 50
C222 22 50
C280 10 50
Located on the Remote Adjustment Board
C332 10 250
Located on the Neck Board
C402 470 35
C403 100 50
Not present on all PCBs
C406 1000 35
C407 100 50
C408 100 50
C409 100 50
C411 22 50 BiPolar Cap
C451 22 50
C455 10 50
C456 10 50
C457 10 50
C458 22 50
C459 22 50
C503 100 50
C513 10 250
C515 100 250
C554 1 50
C556 1 50
C561 47 50
C562 100 50
C911 1000 200 Filter cap
C951 180 100
C952 220 100
C953 47 250
C954 680 35
C955 220 50
C956 680 35
C957 10 50
C958 47 50
C987 10 50
Not present on all PCBs
Some chassis PCBs are missing these ceramic caps – installing them can reduce EMI/RFI interference from AC power
C991 1000 pF 400 Ceramic
Kemet C911U102MVWDBA7317
C992 1000 pF 400 Ceramic
Kemet C911U102MVWDBA7317
C994 1000 pF 400 Ceramic
Kemet C911U102MVWDBA7317

Restored Missing Files in the “PC Software” Section

 General  Comments Off on Restored Missing Files in the “PC Software” Section
May 012024
 

The files in the “PC Software” section of JAMMArcade.net had been lost in a WordPress hiccup some time ago. Thanks to augitesoul sharing his backup of the files with me, they have now been restored.

The files hosted on that page are:

  • A09 Konami-1 cross assembler
  • BINman
  • BINPatch
  • CalcSig
  • ROMCMPGUI
  • TAP2WAV
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