Hi Michael, To put what you are asking a different way, if the "E" bit for an interrupt source is reset (equal to zero) and the interrupt request is received (setting (equal to one) the "F" bit), is the interrupt acknowledged (ie jump to address 4 and execute the interrupt handler)? The answer is no. You can test this out in the simulator - Enable TMR0 to run from the internal clock (ie write 0x0D0 to OPTION_REG) and wait for the timer to roll over. You will see T0IF (the interrupt request for TMR0) become set, but execution will not jump to address 4. It will only jump to address 4 if T0IF, T0IE and GIE are all set. Does this help? myke ----- Original Message ----- From: "Michael A. Powers" To: Sent: Tuesday, August 27, 2002 10:24 PM Subject: [PIC]: Interrupt Enable Flags - quick question Let's say I set an interrupt enable bit to 0. While the interrupt is disabled, an event occurs which raises the interrupt flag. Once the enable bit is set to 1 (and the flag has not be reset), is the interrupt called? Thanks. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details. -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.