I want to count how many times a transistor triggers per minute. It's important to not miss any triggers, so my assumption is that an interrupt is necessary. I've never used interrupts. I'm using a Arduino 2560, and a TCRT5000 IR emitter / photo transistor that is reading a reflective patch on a rotating shaft (One trigger per revolution, want to display RPM). It makes sense to me to count pulses per second and calculate RPM. RPM could be as low as 100 or as high as 10,000
What's the best way (accuracy) to go about this?