"It was always nice though, that in the field, one could write debugging code and test code on the fly."

A laptop with a C-compiler and a device with a Cygnal chip on board is a very good alternative. Mind you, no solution is perfect when you're in the middle of an actual field in the middle of a hailstorm, like I was last week... :o(

I too have used the 8052 Basic for many years, but like you say: Demands have outgrown its performance. Still, it's a very good introduction to embedded systems. It would be nice if something like the Basic Stamp could be introduced based on the 8052.

Rob.