#: 17894 S12/OS9/68000 (OSK)
    11-Apr-93  19:16:09
Sb: #MM/1 disasm
Fm: Bob van der Poel 76510,2203
To: all

I've been wasting a bit of my time looking at disasms of some of the mm/1
system code. I'm confused by the way some of the ports are addressed. For
example, I see stuff like:

        move.b $9ffc01,d0

Which, I know, means to move a byte from $9ffc01 to register d0. However, are
not all the ports addressed at EVEN memory addresses? Don't know why I figure
that...I just figured it.

So, assuming that there is a device with its base addresses at $9ffc00, just
what is at $9ffc01? BTW, the mm/1 tech man suggests that the MC68901 on the
main board is at $9ffc00.

I must be missing some important hardware concept!

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