Measuring motor speed and display result on LCD using ATmega8 microcontroller

For measuring motos speed there can Optical interrupter used like H21A1. This is a device where IR LED and photo-transistor is coupled in to plastic housing. The gap between then allows interrupting signal with opaque material and this way switching the output from ON to OFF. This device can be connected to Microcontrollers ICP pin

Measuring motor speed and display result on LCD using ATmega8 microcontroller is a post from: ATMega32 AVR