> When you read the port the second instruction, the PIC
>reads the state of the port in hardware, the capacitively loaded pin is
>still changing state, then the pic WRITES what it reads to the port.  Thus you can tell a pin to go to zero, immediately read it, it is read as zero, then come back later and it is 1 and you say "What the F()&%#$&*&#$???"

BTDT, it sucked.

This is a foible the AVR is blissfully immune to.

The AVR has DDR (Data Direction register) PORT (output) and PIN (input) registers, so I can do anything I like on the PORT, to set outputs, and the PIN reads me what they are actually doing.

If I set a port pin high, which is shorted to ground (or has a large capacitance) then the PIN bit will read 0 but PORT will remain a 1.

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