Williams "all in one" Rottendog PCB (system 3-6)

[BallyWilliams suck]

Hi All

I have a pcb that's come in today, with U36 missing. It's a dip40 ic - and looking on the schematics, I can't seem to work out if this a custom chip - or even should be populated. Does anyone have one of these PCBs they could have alook at please? It's in the top right below the 74hct154n.

Thank you !

James

 

[pinballmania]

Its just a 6821 according to this pic

https://www.pinballlife.com/rottendog-williams-system-3-to-6-mpudriver-combo-board.html

 

[BallyWilliams suck]

Thank you for the reply - I did check the schematics and it wasn't listed as a 6821. More dodgy Rottendog schematics!