The lowest frequency acknowledged by PBP is 3.579MHz (color burst crystal) OSC=3.
Anything lower must be interpellated.

For instance, at 1 mhz, a serial signal that would work at 9600 baud at 4Mhz, would act as 2400 baud with 1mhz.
So setting a USART, or SERIN(2) to 9600 baud, will give 2400 baud.

A PAUSE 100 would actually be PAUSE 400.

Everything gets adjusted by, 4:1
Just set OSC to 4, and adjust proportionately.

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