I just resurrected a -17 MPU and all is working fine with the exception of the credit display data showing up identically on the Player 3 display. U20, pins 2,7,9, and 11 are the display latch strobes. The U20 chip is socketed and it looks like pin 2 (player 3 strobe) is crispy at the solder pad despite continuity checking out ok. Checked for short between pin 2 & 11 (credit display), none. There's nothing obvious like solder splash and unfortunately I can't read what type of chip this is, but manual says hex buffer 14502 (B) or (8)? Can't tell.
I swapped the PIA's, no change. I have 2 other working -17 MPU's where this is not happening, so def on the board.
Has anyone run into this issue before?