Need 4 modes with just 3 switches - need all modes to be selectable QUICKLY!

[Kamikaze47]

Kamikaze47 - I'm using the PIC's own weak pullups internally (to save using pullup resistors externally) - so for all it looks to be, it's not a 'short' of 4.1V to ground through the diode when the switch is pressed, but a path as follows...

4.1V->PIC Internal Weak Pullup->Diode-> ground. (most of the voltage is dropped across the internal weak pullup)

(and not all the PIC's pins have weak pullups internally ...this was something else that imposed a restriction on me!)

Ahh, right. I was assuming you were setting that pin high. Makes sense now.