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Re: Apple II VGA Video Generator Card Project



Alex Freed wrote:
Michael J. Mahon wrote:
 >

But that will require a "flying cable" from the card to the keyboard
connector, and a switch matrix emulation for machines prior to the
IIgs and an ADB emulation for the IIgs.


I don't agree. Apple 2 uses an ascii code from a keyboard. A 7 bit code with the MSB indicating that a byte is ready. No switch matrix to emulate. That is a pain in the butt as I know from a ZX Spectrum in an FPGA project.

However I don't think USB interface for a keyboard is called for. Most keyboards in non-Mac world use a PS/2 interface that is infinitely easier to support.

Yes, but the //e uses a switch matrix interface--the encoder is on the
main board.  (Sorry for saying "prior to the IIgs" when I meant only
the //e--it's just that there are so many more //e's than ][ and ][+
machines.)

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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