Repair IGS PGM rev 14 MB - ERROR 68K:ED56 Z80ADDR:C10000 DATA: ED46

[digitron]

Hello,

Curious if any of you, especially @GC8TECH have ran across this error on your IGS PGM board and if you were able to repair it?

Green screen, then: ERROR 68K:ED56 Z80ADDR:C10000 DATA: ED46

Sometimes I'm able to get the motherboard to show if I bump the voltage up to 5.2v or so but not reliably. I also noticed there is coil whine from the PSU with this IGS PGM motherboard but not with my J-PAC.

No game cart plugged in, Jamma edge @ 5v.

http://imgur.com/a/R2n8W2w

 

[GC8TECH]

Thats a easy one. I've had that before... You need to replace the Z80 SRAM. Its 12ns SOJ package.

Lives down near the jamma edge. If you still not sure were it is i'll send you a pic with it in latter tonight after work...

T.

 

[digitron]

TY @GC8TECH !!

WOW!

Just re-flowed the solder on these two chips and guess what......IT'S WORKING!!!

Cold solder joints all over these PGM MB's, figured what the heck. MB booted right up @5v.

@GC8TECH you're awesome bro, tyvm!

 

[GC8TECH]

Attached is the pic i was going to send you... the pic is of ram i replaced. It can be 15ns OR 12ns.. But 12ns is a better choice

I was going to ask for a picture of the error before you fixed it

T.

 

[digitron]

Yep, those were them. I added a pic of the error to the OP, thanks again!!