deramp5113
Veteran Member
Looks like address line A4 is stuck high or stuck low. Since the monitor ROM seems to be working fine, then it's probably not a problem with the system bus or an address buffer on the ROM board (assuming the monitor ROM and the MZOS ROM are on the same board). Most likely, it's a pin/socket problem with the MZOS ROM and socket. Pull the ROM and reinsert it a few times to scrape the pins/sockets a bit. Be careful though - don't want to damage that chip - seems to be pretty rare!
If the duplicate "row" problem goes away when dumping from the monitor, then dump the ROM through the serial port again. Thanks!
Mike
If the duplicate "row" problem goes away when dumping from the monitor, then dump the ROM through the serial port again. Thanks!
Mike