Salam , hello , hey.
what happen during an interrupt? .. i know the pc and stack pointer and main program interrupt issues. What iam asking is if controller 8051 is set to scan a port when ever a timer interrupt over flows after 10 milli seconds, now the timer is not stopped any where in the program, the timer is in the main program and when ever it over flows, port is scanned at its vector address. Now during the scanning if bit 1 is set and the program jumps to the address indicated by that bit and there is a task which that bit has to perform. Now during this bit task process , timer is over flowing again...now when the timer over flow now will it effect the the process started by bit 1 since bit 1 task is not in the main program.