Is it a given or an almost given that if an input/output on a TTL chip sees 12v that its toast? I was working on a Space Invaders board yesterday and found it had a smashed trace, sending 12v into one of the address bus lines (A1). The board had no roms installed at the time. I know one chip got hot enough to pull my finger away (9233@F6) and I know the address buffer (74LS08 I think) saw 12v, but at this point both chips seem to at least have a signal although the boot isn't booting.
Just wondering if I should just shotgun those chips.
Also - the DMI/Hold pin on the CPU is low, causing the cpu to go into "disconnected" mode - is that normal for no roms? My test rom didn't seem to work but I need to replace the CPU and rom H sockets first I think.
Just wondering if I should just shotgun those chips.
Also - the DMI/Hold pin on the CPU is low, causing the cpu to go into "disconnected" mode - is that normal for no roms? My test rom didn't seem to work but I need to replace the CPU and rom H sockets first I think.

