Hi mackrackit

But if you want to read ahead...
I'm with you, reading ahead is ok but learn to walk then run (or crawl then walk in my case).

Just out of interest would the ARRAY idea have worked?

This code is just an idea, is it on the right lines?

Code:
SERIN2 PORTC.5, 16780, [DEC NUM1] 'MODE 16780 = 2400 BAUD INVERTED

SERIN2 PORTC.5, 16780, [DEC NUM2] 'MODE 16780 = 2400 BAUD INVERTED

LET TOTAL = NUM1 + NUM2

SEROUT2 PORTC.3 TOTAL