generate interrupt

Discussion in 'Embedded Systems and Microcontrollers' started by midoman, Mar 21, 2007.

  1. midoman

    Thread Starter New Member

    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)_____
  2. Papabravo


    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.