Design of a high performance digital tachometer with a microcontroller

The design of a very flexible, low-cost speed evaluation system is presented. The system provides fast dynamic response and high accuracy over a wide speed range. The design is suitable for a broad range of applications and can be integrated as part of an existing tachometer assembly. Hardware requirements and appropriate software structures for a microcontroller implementation are discussed. The algorithm used to calculate the speed is based on the method of constant elapsed time. The predicted performance is verified experimentally