Konami '502' reproduction

Another custom IC successfully reproduced.It's the one found on Konami PCBs and labeled as '502' in schematics but with scratched-off part name like this manufacturer is used to do.It's a 28 pin 600mil IC :

You can refer to this useful spreadsheet (credits to ‘mattosborn’ on KLOV forums) to check which boards use it :


Konami custom ICs

I made a first replacement using simple TTL gates:

I tested it with on a Track & Field PCB, it worked fine :

So, happy with result, I ported the design into my own 28 pin CPLD board :

Here's the final successful test after some optimization work  :