Re: Apple II mistery card...

[mjmahon@aol.com (Michael J. Mahon)]

"a" wrote:

>Please post a picture of of both sides of this 6522 (VIA) card if you can.
>I'm interested in building my own card with a 6522 and need to know
>if the phase-0 clock signal on pin 40 of the peripheral bus needs to be
>"delayed" before the 6522 sees this signal as phase-2.
>A photo of both sides of this card would help tremendously!

There is typically a small RC delay network on Phase 2 to interface
a 6522 to the Apple bus.  A gate is usually used to buffer the delayed
(and rounded) signal before driving the 6522.

-michael

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