retrolefty:
Does changing the interrupt direction to raising edge give the same behaviour?//external interrupt 1 on falling edge
Lefty
Yes, I tried that too. Just verified it again as well.
I found these two comments in an application note, but they don't fit the scenario here. It looks to me like enabling the interrupt causes the interrupt.
- When changing the ISCn bit, an interrupt can occur. Therefore, it is
recommended to first disable INTn by clearing its Interrupt Enable bit in the
EIMSK Register.- Before enabling an interrupt, it is recommended to clear the flag bit of the
corresponding interrupt because when the flag bit is set, the interrupt will be
triggered the moment we enable the interrupt.