Repair Logs – Page 106 – JAMMArcade.net

X Multiply repair log #3

Aug 112014

Yes, again.
During some playing of this recently repaired board the game froze up.
On reset I was greeted with this static screen.

Non booting boards are generally quite easy to fault find but due to the V30 I was having problems. This is when I came across a post on KLOV from some time ago with someone asking if an 8086 Fluke POD could be used to test a V30 based system. The general thinking was that it could but no one ever tried it, until now!
Im pleased to say it does work (excluding the RUN UUT function).

Very quickly I found that the main ROM’s could not be read properly. The correct signature was 6A03 and I was getting 6935.
Following my schematics I found that there is a 74LS373 at location IC51 that is used as the latch to address the ROM’s.

This input was confirmed good but there was a stuck bit on the output.
I replaced this and the game was back once again. Ive left this soak testing and hopefully it will be rock solid now.

So just to confirm. The 8086 pod for a Fluke 9010/9100 can be used to check V30 based systems.

Cadash repair log #1

PCB Repair Logs, Repair Logs Comments Off

Aug 062014

This one came from the same lot of faulty PCBs (seven in total) as the previously repaired Growl.For the uninitiated, Cadash is an action game with some RPG elements.

Board was in good shape (it has also additional hardware for multi-link game) .

When powered on I got this screen:

There was a clear problem with main code execution so I dumped the four program ROMs and none of them matched the ones in MAME.I ran these dumped ROMs in MAME and I got a similar error (different memory address due not perfect emulation of 68000 core, I guess):

This was enough to lead me to reprogram the four program ROMs from cadash World set into 27C010 devices.And this was the winning move which fixed the board.

Growl repair log

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Aug 062014

Yesterday I got a lot of faulty original PCBs.Among these there was a clean Growl PCB.I always like this game (and played it in MAME) where the player controls a forest ranger who must protect the local wildlife from a group of evil poachers who are driving the animals to extinction.

As said, PCB was in mint state:

but once powered up it showed garbled sprites:

I noticed that, if I press the PCB in the area near the ASIC marked ‘TC0540OBN’ @IC25, all the sprites were restored.

So ,after a quick consultation of MAME source that confirmed this ASIC as a sprites generator ( the letters ‘OB’ in the ASIC name stand for objects a.k.a. sprites), I understood this was the way to follow in my repair.Probing the tightness of the individual pins with a needle I found some lifted ones.A reflow with my hot air station at 390° and a bit of flux was enough to fix the sprites issue completely.

X-Men repair log #1

PCB Repair Logs, Repair Logs 2 Responses »

Aug 052014

Got today in the mail this mint original Konami X-Men PCB bought as faulty:

Once fired up I got this:

So, RAM/ROM test reported a bad IC @37F but this was not the real location of the IC since there was no location 37F on PCB.So, clearly there was some trouble in the tilemap generation, this was confirmed by the word “BAD” which became “BCF”.So, I launched MAME:

and, comparing the emulator and real PCB test results screens, I could identify that the faulty IC reported by test was the Panasonic MN4464 (6264 compatible) SRAM @ 15F

This confirmed my theory about bad generation of tilemaps since this SRAM is used by the near ‘052109’ ASIC (tilemap generator).

So, time to desolder the IC and test it out of circuit corfirmed the RAM as bad:

Fitted a socket and a spare 6264 SRAM and I could add also this cool game to my growing collection!

Lethal Enforcers repair log #2

PCB Repair Logs, Repair Logs 2 Responses »

Aug 012014

This is the second Lethal Enforcers PCB I fixed and also in this case it has been a pretty easy repair .

Board was mint and clean:

When powered up it I got this screen:

Screen was static but from the clicking sound I understood that watchdog was active so, for first, I disabled it by closing jumper ‘JP’ near JAMMA edge.In this kind of Konami hardware (like in many others) RESET is generated by pin 10 of the SIL custom ‘051550’.Probing this revealed that signal was good (first LOW and then HIGH) while RESET line (pin 37) of the main CPU HD63C09EP was stuck LOW.I traced it back to a 74LS367 @N6 which output was good and input of this to an output (pin 13) of 74LS164 @H3.Tested this with HP10529A logic comparator revelead bad outputs (pin 11, 12, 13).

So I desoldered and tested it in my EPROM programmer and B&K Precision 560A IC tester which confirmed it as bad:

Replaced it fixed the board completely.

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