Re: PS-2 Keyboard for Aplle II ?

Linards Ticmanis wrote: 
Jay Maynard wrote:

That depends. Just what does an Apple ][ keyboard look like to software?


Plain 7-bit ASCII of key appears in address $C000, whenever the high bit is set it means a key has been pressed. Accessing $C010 clears out the previous key and allows a new one to be received. 

While the Apple main board takes care of the $C010 keyboard strobe, the
keyboard adapter/encoder must supply a "new key down" strobe in addition
to the 7-bit ASCII.  This will do it for a ][ or ][+.

For the //e, it is trickier, since the //e keyboard connector interface
is an unencoded keyswitch matrix plus a few unmatrixed keyswitches.  It
would be trickier to emulate such a keyboard with a microcontroller,
since it would have to sync with the main board encoder scan.

-michael

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

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