Update:

After sorting out my SerIn problem (i didnt know SerIn waits for eternity until data arrives), I managed to get my Serial to 7-seg project 'roughly' work.

However, due to to the time it takes to read/wait for SerIn data and go back to multiplex the 7-seg displays, i dont think this will EVER work in the correct fashion i anticipated.
If i shorten the timeout on SerIn then i miss incoming data, if i lengthen the timeout to get data, then the 7segs are too flickery.
With several adjusments, i have PERFECT 7seg multiplexed displays but with no ability to read SerIn data.

So, I don't think i have any option but to upgrade to a Pic'877 (i have a boxful) and use 2 ports for the 2x 7seg displays, where they can hold LATCHED data onto the 7segs, whilst the SerIn can be left to sit for eternity waiting for new data without upsetting the 7seg displays.


I encourage anyone who thinks they can make it work to prove me wrong

Regards,
Marty.