On Mon, 21 Nov 2005, simcop2387 wrote:
thanks to the source to the disk rom i was able to verify that the
emulated cpu is working properly (i could be wrong about that).
what i don't know yet is why when it reaches the end of the rom it jumps
to $0801 (which ends up filled with garbage it would appear when looking
at the contents of the memory thanks to the apple monitor).
Because that's where the boot sector is loaded off the disk.
I'm tempted
to just skip the disk controller and go with creating a nice gui for
stepping through everything easily, and watching whats going on (and any
place in memory) so i can see whats going on and try to learn why.
the disk image works fine in the original java emulator (until it
crashes)
so i'm thinking the problem with the disk controller (since i borrowed
the
whole thing) has to lie in either my IO code or my cpu core (which
doesn't
seem like the case, it runs the monitor and basic fine, though i don't
know how to properly use the basic at the moment)
anyone anyone have any specs about the whole disk controller that might
help in verifying whats working and what isn't?
I just used (in Dapple and SDDapple) code from a public-domain Apple ][
emulator written by Andrew Gregory in order to implement the disk
interface. Basically you need to handle reads and writes to $C06x
specially.