PIC18F47K40 Interrupt issue on Falling Edge
Posted: Sat Dec 26, 2020 10:15 am
Hi all.
If I use an Interrupt active on Falling Edge on INT0 Pin with a 5,6 Kohm pull-up resistor and a normally open push button from INT0 Pin and ground, as soon as I power the Pic, the Interrupt get fired, even if I don't press the push button. Tryed some delay before the interrupt's icon but the problem was still present (500 mS and 1 sec.).
If I reverse the logic, with Interrupt active on Rising edge, a pull down resistor and the push button from the INT0 Pin and +5 Volt, the problem disappears.
The same for INT1.
Tested on real Hardware. Attached a very simple program that turns on a led when the interrupt get fired.
Can someone tell me why and if I'm doing something wrong?
Thanks
Rov
If I use an Interrupt active on Falling Edge on INT0 Pin with a 5,6 Kohm pull-up resistor and a normally open push button from INT0 Pin and ground, as soon as I power the Pic, the Interrupt get fired, even if I don't press the push button. Tryed some delay before the interrupt's icon but the problem was still present (500 mS and 1 sec.).
If I reverse the logic, with Interrupt active on Rising edge, a pull down resistor and the push button from the INT0 Pin and +5 Volt, the problem disappears.
The same for INT1.
Tested on real Hardware. Attached a very simple program that turns on a led when the interrupt get fired.
Can someone tell me why and if I'm doing something wrong?
Thanks
Rov