Addressing with Dip Switch or ???

[tazntex]

I am using an rf module, the transmitter is addressed the same as the receiver using a dip switch. My question is if I use a dip switch is this the best way to separate identical units or is there another option? And if there is a better way, what would the maximum addresses I could have be? I am using a 16F628A with three available I/O pins.

Thanks