On 24/05/2018 07:24, Jim Brain wrote: > I think it's going to be tough to pull the Z80. Bil Herd notes in his > stories that the C128 bootup relies on the Z80 pulling startup vectors > from low memory to handle carts like Magic Voice that play with the > control signals when 6502 vectors are pulled. It depends on what magic voice is looking for. The 6809 resets by jumping to the address stored in fffe/ffff, 6502 resets by jumping to the address stored in fffc/fffd, while z80 jumps to 0. The 6502 jumps to the address stored in fffe/ffff when taking an irq, so if that also triggers magic voice then you have a problem. It's pretty clear you don't ever want to page the 6502 kernal rom into the 6809 address space either because the irq's conflict terribly.Received on 2018-05-28 16:00:03
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