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Re: Hardware musings



Justin England wrote:
"Lyrical Nanoha" wrote ...

On Sat, 14 Oct 2006, BLuRry wrote:



Lyrical Nanoha wrote:

Just been thinking while we're on the topic, mightn't we need to have an
actual 6502-class CPU somewhere in the loop for timing reasons? This would
essentially turn the disk ][ / Unidisk into something more like a 1541
though.


A 6502 needn't be in the loop, just something capable of doing the timing required by the disk ][. But yes, it would turn the disk to into nothing more than a USB device connected to a PC. What keeps me thinking that it could be done, is that only "half" the disk ][ interface needs to be "emulated" since it doesn't need to talk to an a2.

The only thing you can really eliminate is the boot ROM.  The software
will still have to run the 2MHz state machine and communicate with the
PC to dump off nibble streams (that the PC could decode/encode with its
own RWTS.  Essentially every function that exists in the Apple must be
provided--except the boot ROM.

Of course, if you'd like a PC emulator to be able to use the emulated
drive like a real drive, then the emulator would also have the boot ROM!

-michael

NadaNet networking for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

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