Thanks for the reply JohnInTX. For such application, is there the need to enable TXIE and RCIE ?

Not if you are polling the comms as in your first post. Enabling the interrupts without interrupt handlers is a bad thing.

Eventually, you should use interrupts and FIFOs.

 

I think much depends on what kind of data, expected size, frequency etc and responses needed etc.
But as as rule I use input interrupt at least as this avoids constant polling.
Max.