I interfaced 64Kb of external memory to my C167CR at base address 0x80000. That memory consists of two 32Kb chips. The memory is \CS2 selectable and I want to use the A15 pin of the address bus for bank selection (second chip to be enabled for any address above 0x88000). That configuration with the A15 pin seems to have problems. Is there something that I probably don't know about that attempt?