> I am using a 16F716 with all portb pins tied to ground through 20k
> resistors.  I have also tied portb(4..7) to Vcc through switches and 1k
> resistors.  I use portb(4..7) to address a mux and portb(0..3) to drive
> relays through a buffer.

Please make the circuit a little bit more clear. Where are the
resistors? Which MUX?

> Here is what I have tried so far (sorry for the parallax):

And you should be. Unfortunately I can't help with the code, as I am
not entirely sure what the instructions do exactly. If they do what I
think they do, it should work fine, however, they might do something
else. MPLAB compatible code is a wiser choice.

> I am wondering how to do this and whether it is possible without affecting
> the outputs driving the relays on portb(0..3).

Given that the 16F716 has an 8-bit analog to digital converter, I
would recommend hooking all the switches up to that: you're using
resistors anyway. Give each switch a different resistor value, use the
AD converter to sample the result and there you have your switch
status, using only 1 port.

Greetings,
Maarten Hofman.

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