IO access differences in MD mode vs SMS
Posted: Mon Oct 01, 2018 1:42 am
I’m in the midst of a project and was wondering if the bus
Arbiter / IO chip disables PORT access to the various peripherals from the Z80 or if it leaves that access available in addition to the memory mapped access? If it leaves it enabled could you get in a weird situation where the 68K is reading or writing the controller direction register while the Z80 side could be modifying it via PORT?
Arbiter / IO chip disables PORT access to the various peripherals from the Z80 or if it leaves that access available in addition to the memory mapped access? If it leaves it enabled could you get in a weird situation where the 68K is reading or writing the controller direction register while the Z80 side could be modifying it via PORT?