Small motors, less than 300 W, are found in a wide variety of applications, including automotive, robotics, factory automation, test equipment, and space and military. The C8051F3xx series of small form-factor microcontrollers (MCUs) is well suited for the control of these small motors. In addition to the standard 8051 timers, the C8051F3xx series also features a programmable counter array (PCA) with several operating modes. It also has a digital crossbar that can be used to select which port pin receives the PWM signal, and its analog-to-digital converter (ADC) can be used to measure the motor current, supply voltage, back-emf, and temperature of the motor. The C8051F3xx family also features a two-wire C2 interface that permits Flash programming and debugging.

The purpose of this application note is to provide software examples using the F3xx MCUs to control various types of motors. The examples may be used as a starting point for the development of more complex motor drive systems.