Originally Posted by Jebarus

While doing this implementation, I improved the precision of the electrical RPM sensor quite a bit. It was accurate before, but noisy. Now, the sensor is super precise, with pretty much no delay. At 20kRPM, the interrupt triggers every 0.0015 seconds, and the sensor measures the time between interrupts with 0.000004s accuracy. I am using the interrupt with timer 0 on the Atmega 328. The signal is very smooth. The following image is the graph of the two sensors. There is no low pass filters.