I am trying to generate a pulse to trigger an interrupt when the input changes state.
High->Low & Low->High
The input is a reed switch.
I'm using a XOR gate (SN74AHC1G86QDBVRQ1) with an RC delay on one input.
GPIO2 is used for detecting the state of the input after the MCU wakes from the interrupt.
The circuit works correctly when changing from Low->High. When changing from high to low, it will only work when a scope probe or another metal object is touching terminal 2 (GPIO2).
Does anyone have any suggestions on why this is happening?