This application note describes a 3-phase synchronous permanent magnet motor control software library developed for the ST7MC drive with sinusoidal waveform. The ST7MC microcontroller contains a peripheral dedicated to 3-phase brushless motor control, making it suitable for AC induction motors and permanent magnet DC/AC motors (PMDC/PMAC, also called BLDC). The library described here is made of several C modules that contain a set of convenient functions for the generation of the sinusoidal waveform, the synchronization mechanism and closed loop control of PMAC induction motors and is compatible with both COSMIC (www.cosmic-software.com) and METROWERKS (www.metrowerks.com) compilers.