Hello!
My 8052 program works fine in the Keil Simulator, butwhen I run it on the actual ADuC812 chip, all that happens is that P2 pins go low. When running it in the debugger the same thing happens, and when single-stepping in the debugger, instead of pins going high or low as expected, for each of the first few steps on one pin I actually get a lot of activity (i.e. varying from high to low), and then a communications error appears, although I believe I have everything set up.

I can't think what could be wrong. can anyone help? please!

Cian.