I've gone through the picNpoke tutorials, and now i have a few questions.

1) What does open collector output mean. What should i consider in the
circuit diagram for this pin.
2) What does weak pull-ups mean.
3) Is there a latency between setting a pin to high and when it actually
does go high, and if there is, what should my minimum time delay be if i
want to take it high and low very fast - ie 400ns ( 10 MHZ low instuction
immediately after a high )
4) if RB7:4 is set to interrupt and RB5&4 are to outputs, will i
inadvertently generate an intterupt when i write to bits 4 and 5.
5) does anyone have a 5digit bcd to 16bit binary routine please. My mind is
going numb trying to work that one out. i can do it on paper though

6) I want to use a pic for a dimmer switch. what is the easiest way to tap
5vdc from a 220vac line. I want to mount it inside the light switch cover if
at all possible.

thats all for now

thanx in advance

 John