Hi

With Timer2 I'm trying to time how long it takes for any data being recieved on the serial to be recieved.

Ok the task is - to have an RTC, to have that RTC updatable throught the serial port from a PC (so if you want to change the time you have to do it through the computer) and finally to have a counter, time how long it takes for the update (so as soon as the RTC is interrupted by the MCU detecting something waiting in SBUF the timer is started and runs until you need to switch back to the RTC)

I want the timing to be as accurate as possible and I guess the minium would be 0 and the maximum would be whatever value was stored after the MCU has completed its receiving of data on the serial and turned the timer off.

I hope this describing makes more sence of what I'm trying to do.

I've read and reread the tutorial on interrupts and I still can't figure out how to "interrupt" the RTC receive data on the serial port and time it at the same time. The only thing I can work out is how to EITHER recieve data on the serial OR do the timer I can't figure out how to do BOTH at the same time.