Here's the jumper info you need for the Bally MPU:
https://www.pinwiki.com/wiki/index.php?title=Bally/Stern#Bally_AS-2518-35_or_AS-2518-133_Jumper_Info
Quoted from T-Tommy:I saw this pic with e12 connected to e9.
I created that picture.
I hated the idea of running a long wire from E12 to ground. When I checked the schematics and mapped the U2 ROM address space, tying U2 pin 18 (E12) to address line A11 (E9) made logical sense and looked more elegant.
Low and behold it was already official:
http://www.planetarypinball.com/mm5/Williams/tech/bally_read1st.txt
Wanna join the discussion? Please sign in to reply to this topic.
Great to see you're enjoying Pinside! Did you know Pinside is able to run without any 3rd-party banners or ads, thanks to the support from our visitors? Please consider a donation to Pinside and get anext to your username to show for it! Or better yet, subscribe to Pinside+!
This page was printed from https://pinside.com/pinball/forum/topic/bally-mpu-conversion-to-2732-sconnect-e12-to-e9-?hl=jethrop and we tried optimising it for printing. Some page elements may have been deliberately hidden.
Scan the QR code on the left to jump to the URL this document was printed from.