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Re: Hardware musings
- Subject: Re: Hardware musings
- From: "Michael J. Mahon" <mjmahon@aol.com>
- Date: Sun, 15 Oct 2006 02:58:42 -0700
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Mark McDougall wrote:
Justin England wrote:
It should be fairly easy to find a USB to TTL device that could talk
to a PIC, and the PIC could directly manage the drive.
You can get PICs with USB built-in!
Again, I have forgotten most of what I knew about A2 hardware, but I
can't imagine it being horribly difficult to "emulate" a disk ][
controller with a PIC considering it should have to ability to do the
timing critical functions.
I'm not intimately familiar with A2 hardware myself, but anything that
can be done in TTL shouldn't be overly difficult, though you're best
looking at a CPLD methinks...
If you can write a program to sample the disk read signal at a 2MHz
or faster rate, and implement the state machine within that loop, then
the entire controller can be emulated in software in real time.
-michael
NadaNet networking for Apple II computers!
Home page: http://members.aol.com/MJMahon/
"The wastebasket is our most important design
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