The '005924' is another custom IC from Konami used on arcade PCBs of the mid / late 80s like :
- Nemesis hardware
- Twin 16 hardware
- Contra
- Jackal
- Combat School
- WEC Le Mans 24
The chip comes in a ceramic SIL package (11 pin) covered by epoxy :
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Technically speaking the '005924' is for main CPU reset generation, it acts as watchdog timer and handles coin counters, too.
Recently I have been asked me too look at this chip in order to made a replacement that would help people to fix their boards with faulty '005924'.
An arcade collector friend of mine sent me a chip which he had started decapping (thanks to him!) :
I continued the work and exposed all the ceramic package drawing the schematics at same time.Then I routed a board layout :
Gerger files were sent to manufacturer and, after received the bare PCBs, I populated one with the needed parts :
The test on an Hard Puncher PCB (Twin 16 hardware) was successful, here's a video showing that all functions of original custom chip (including the watchdog timer feature) were correctly implemented in the reproduction :
