For both text areas I would create a combo in
order to select the way they show data: ASCII, HEX or
both. If you select the third way cutecom should
duplicate (horizontally) both areas in order to have a
parallel view of the data (one for ASCII and another
for HEX bytes).
It's very useful when you're working with AT commands, for example (i've been working with a GPRS modem, and all communication is done in this way). It's interesting to see both ASCII output (the commands) and HEX output (probably some "extra" byte that appears in the channel (sweepings) and you don't know where it comes from (it's usually a 0x00 byte, and it's hard to identify in ASCII mode).