When trying to run a program under the latest version of the uVision2 debugger (v6.12), the simulator keeps halting with the error box "Port 1 Error - You have tried to modify a port pin which is configured as output!". Although the message looks clear, I don't understand its meaning since the area of code where it happens doesn't have any Port 1 accesses! The error also doesn't occur when single-stepping, only when running at full speed. It looks like a bug in the simulator. Can anyone else shed any light on it? (Unfortunately my program is pretty big, and I haven't managed to replicate the problem with a small code fragment, so I can't (yet) post the offending code).