generate interrupt

Thread Starter


Joined Mar 21, 2007
can i konw a method for generating external interrupt for the 8051 when the the data on a latched (74hc573) input port changed for a 8051 input port
__ new data -----------> generate interrupt(int0 or int1)_____


Joined Feb 24, 2006
Sure. Run the latch enable(LE) signal from the latch to INT0 or INT1. Set the interrupt to trigger on the negative edge. When the latch enable goes away new data will have been loaded. If you want to keep track of successive loads then compare the old reading with the new one and return from the interrupt if there is no change, or process the changed value and then return from the interrupt.