Hello! Mia Magnusson wrote: > If the IPC code is in bank 15, then the incorrect write would end up at > adress 0 and 1 in bank 15, which I assume is not a place where the 8088 > wants to read/write from disk. So the 6509 IPC disk I/O code should > work even when crossing page boundaries. Yes, but the write to address 0 also ends up in the CPU register, which is the execution bank. So the CPU suddenly jumps to some random bank and of course there is no valid code there, therefore it hangs. > P.S. does VICE emulate the 6509 behaviour correctly? Although there are > no 8088 emulation there, afaik it has a monitor making it possible to > check what happens anyways. All the tests I've written so far run in VICE correctly. It's, however, not possible to peek into the memory at $x0000 and $x0001 with VICE's monitor because it always displays the CPU register there. So it's hard to say what is actually getting written to the memory in this case, and whether it even makes any sense to think of such writes. Regards, Michau. Message was sent through the cbm-hackers mailing listReceived on 2018-02-26 11:01:15
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