Field oriented control (FOC) theory was the most common control method for permanent magnet synchronous motor (PMSM), which required instantaneous position of the rotor. This limited its application to brushless DC motor (BLDCM) using Hall position sensors. In order to apply the FOC theory to the control of BLDCM without increasing the cost of the motor, based on the existing Hall position sensor, an estimation method of the rotor precise position by calculating the average speed of the previous sector based on the output signal of the Hall sensor was proposed. This estimation method was simulated using MATLAB/Simulink software. The experimental system based on TMS320F28069 DSP was built. The algorithm was programmed by automatic code generation technology. Both simulation and experiment results showed that the method could be used well in the control of BLDCM, and it could replace PMSM in some low cost applications.