Dennis Plunkett wrote:

> When going from RX to TX ,set the data line to an output first (An
> place in the idle state) then change the driver enable. The small
> contention time can be lived with,

  Sorry, but I don't see the point in this.  You avoided contention
in the other direction by disabling the PIC first, using a pull-up to
hold it in idle *then* enabling the receiver driver.

  Why will this same resistor not work if you *disable* the receiver
driver first, *then* enable the PIC output (pre-set to the idle state)?
--
  Cheers,
        Paul B.