I am only using opto couplers because through searching the archives I determined the inputs to the MCU should be protected and my MCU was crashing so I thought I would try this method. I originally had the pickups connected directly to the interrupts but the interrupt routines would end up looping so I figured I should try the opto couplers.

The pickups are composed of two small magnets which sense a small metal plate which spins past the sensors.

If I don't have to use optocouplers on the inputs is there a preffered method?

Thanks

James Krushlucki