There was a thread on this topic just a couple of weeks ago: multiple
bit-banged UARTs.  Check the PICLIST archive.

I have an (untested) implementation that will support 4 UARTs at relatively
high rates and will leave enough time to drive a PWM for the servo (which is
really a very low bandwidth operation).

Bob Ammerman
RAm Systems
(high performance, high function, low-level software)

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