Am 15.02.2013 17:58 schrieb BLuRry:
No, it's not apple related but it begs the question: What would it take to build a similar ISA interface for the // bus?
Apple phi0 is even earlier than 6502 phi2, so more than 150ns delay will be needed. At least the timing GAL has to be reworked to suit an Apple II bus.
The NMI circuit is not needed, you can directly connect /INTx to /IRQ. Patrick