Once again we have some technical info which might be of interest for a few people out there in the wild.
As before "ttlworks" did the written documentation and I "only" Copy&Paste it here in Forum64...
that means the "I" in the following text refers to Dieter actually. He did the majority of work.
So let's start:
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Main threads:
Side quest:
This thread is a comparison of the 6509 and 8501 clock generator, brought to you by Frank Wolf and ttlworks.
Because the official MOS 6509 datasheet contains an error (PHI1 and PHI2 inputs swapped),
I felt a need to take a closer look at the 6509 clock generator.
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Results for the 6509 in short form:
Pin 40 is PHI1_in.
Pin 38 is PHI2_in.
Both pins drive the circuitry inside the 6509 directly/unbuffered.
Each pin has an ESD protection FET.
TTL circuitry for driving the PHI1_in and PHI2_pin of the 6509 can be found in the P500 PET-II schematics .