Recent content by caius

After converting the board from 4 to 2 Players you must re-initialize the serial EEPROM @13B by holding the test switch while powering the board up and keep pressing down it as long as the whole process has ended. Attached is the capacitors chart of the '054544' audio module.

Brilliant job but you had a slip on that tongue twister! ahahahah

I know you have the solution but you were referring to Hammy and the 27020 dumping so I gave a pertinent answer.Again, he can't dump it with this method :)

Sadly it's not easy as you may think.This PLD, altough it's a PAL16L8, uses internal latches (also combinatorial devices can have this configuration) hence every attempt of dumping it as a 27020 will EPROM fail (like it happened to other people me including).A deep analysis/observation of the...

Is this Tecmo ROM board requiring the BIOS board to properly work?

Great stuff!I'm glad (and uplifted too) I got the measurement right!

Some time ago I designed a device that can replaces all the three Namco MCUs marked '60A1' , '63A1' and '64A1', you can read more about in my previous post : Namco '6xA1' replacement The replacement was working fine but I later realized that it could not fit well on certain boards due to its...

The ROM board is the easieast one, the middle and bottom ones are tough.You may think to reproduce the bootleg which is already a reproduction of original hardware with reversed custom ICs but there is no point in doing it unless you use FPGA.

Here's another reproduction I made lately.This time not of a custom IC but an entire board, more exactly the top one (silkscreened 'M-72-ROM-C') from R-Type, the horizontal-scrolling shooter arcade game developed and released by Irem in 1987 and running on 'M-72' hardware. I tried to stay as...

Yes, this is a common issue on Mega System 1 hardware.The 'JK-03' bend very easily but keep in mind that only a row of legs is connected to the internal circuit, the other one is just for support.

Got for repair a faulty original 'P-47 - The Freedom Fighter' PCB, an horizontal shooter originally developed by NMK and published by Jaleco in 1988 running on Mega System 1 hardware : The board was dead, no sign of life, only a steady black screen.First of all I checked with a logic probe if...

Just a quick update about the reproduction of the Konami '051550' custom IC I made time ago : Konami '051550' reproduction The replacement is working fine but, when I did it, I intentionally omitted a part of the original circuit that handles the coin counters/lockouts and gave priority to the...

Sorry but you can't simply by-pass it in this way :) A replacement of the TC0220IOC in on my TO-DO list and I have done some preliminary work, stay tuned!

The Konami '056602' is another ceramic audio module along the lines of the more well known '05498A' and '054544.You can find it on 'GX' and 'GV' system hardware : Konami GX System Konami GV System It's located in the audio section just near the main amplifier : As said, the part has a...

Sadly the dump we have on JAMMArcade is not working because the device is combinatorial but has latches inside and the original dumper didn't know this.Therefore it must be manually reversed.If someone can provide us the chip we can try to reverse it.