Connect two PICs?

[andywpg]

I have a situation where I need to connect two PICs. One is the 'master' and one is the slave. An output on the master goes to an input on the slave (weak pull-up enabled) and I only need to signal two states.

My question is: Do I need a current limiting resistor on that line? I keep vacillating between the two answers, and thought I'd ask the experts.

Thanks,

Andy

[HenrikOlsson]

As long as you don't switch the slave pin to output you don't need a current limit resistor.

/Henrik.

[andywpg]

As long as you don't switch the slave pin to output you don't need a current limit resistor.

/Henrik.


That's kind of what I was leaning toward.

Thanks Henrik

[Dave]

Personally I would place a 4.7k resistor in series with each line connecting the two. That will limit the current to approx. 1 Ma. incase of the software or other malfunction you will not short ether processor pin to +5 volts or Ground.