This paper describes Freescale company’s DSP device MC56F8013 implementation of a fridge compressor control system about BLDC motors without position sensors, which includes motor starting and back EMF running. The motor start-up detects the variation of rotor position according to inductance of stator core. Then when the rotor is accelerated to a certain speed, EMF mode is switched. The EMF mode estimates the rotor position by back EMF zero-crossing detection method. The experiment results prove that the proposed system based on MC56F8013 can work normally and efficiently, and guarantee the demand of domestic refrigerator.