Originally Posted By: JBjorgen
Fascinating. Post back when you successfully flash your first modem.


All sorted, flashed, and appears to be working. smile

The erase/program code worked first time around on both sides (Arduino and Host-PC), but lots of time in the middle was spent working out how to get round the receive bug in the Arduino USB code. A simple brute-force "bigger buffer" solved it sufficiently for this project.

Cheers