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Re: Apple //c++ experiments...



Patrick Schaefer wrote:
Michael J. Mahon schrieb:

(...)   I have several 32MHz oscillators, and found that one type
would not work, while another (RXD 1100) did, so maybe the problem
some have reported is an oscillator problem, not a IIc+ problem...


Some of these oscillators have an output enable pin. You can leave it unconnected, but when you tie it to the wrong logic level the oscillator will stop.

Or otherwise, if anything relies on this function (e.g. to select one of multiple oscillators connected in parallel), it would fail when the OE is not available.

In my case, a scope verified that both oscillators were producing
output (at least with the scope connected ;-), but only one correctly
drove the clock circuits of the accelerator.  Interestingly, the one
that *didn't* work seemed to have a somewhat higher output...

-michael

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