Re: A new pseudo-disk for Apple 2.

Alex Freed wrote:
"Linards Ticmanis" <ticmanis@xxxxxx> wrote in message
news:44c15b95$0$22008$9b4e6d93@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx


Problem with this: On a II/II+ you can't reliably freeze the CPU for
more than about 5 cycles, else it'll lose state.


Sure you can. Softcard does. The trick is that the clock is only removed for
a few microseconds but then
is allowed for one cycle while READY is not asserted. So you can do DMA for
say 80% of all the cycles
and allow the 6502 to fetch a byte now and again.

The problem is that any such solution will increase the complexity of the
board very significantly.

I agree. Using a cannon to shoot a mouse violates one of "Robot's Rules
of Order". ;-)

For heaven's sake, it's a 2-pin pushbutton switch header, and there are
plenty of holes to bring out 2 wires! (I'm assuming that an IRQ/NMI
approach is taken, with an on-screen menu.)

BTW, any reason for choosing the MultiMedia Card over the more common
(and almost interchangeable) SD card?

-michael

New, faster SUDOKU v2.0 solver for Apple II's!
Home page: http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."
.

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