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Can anyone identify this card?

Here's a photo of the front of the board. No manufacturer's markings or numbers on either the front or back of the board!

Apple_II_mystery_board.jpg
 
The 6522 was an i/o chip used in some 8 bit computers. It was used in the Commodore Pet to do the i/o for the parallel port.

The chip has, if I remember correctly, 2 8 bit i/o ports and a 16 bit shift register.

It was difficult to interface to the Apple by itself because Apple didn't put a correct phase 2 clock line on the bus.

You had to take the phase 0 line and run it thru 2 gates to delay it to get the correct timing.

John Bell Engineering made a 6522 card for the Apple that used that technique.

Or you could find the phase 2 line on the motherboard and run a jumper to the card to provide it.
 
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