Interrupt generating circuit: 0 ~ +3.3 V
This circuit will still oscillate if it's moved to a single supply rail. You may have to turn up the gain on the bottom two resistors in the positive feedback pathway. Make sure you select an op amp that is rail to rail or has a high common mode range. 

Interrupts need to be very clean, it would be wise to take the output of this circuit and clean it up with a Schmidt trigger to make sure the rising and falling time is very fast and noise is reduced. The transition time of voltages between Voh and Vol must be kept to a minimum. On some processors metastablity can  result.