I am using an HA13535 three phase brushless motor driver as described in this datasheet: http://www.datasheetarchive.com/dl/Scans-052/DSAIH00045920.pdf The datasheet says the circuit features digital speed control, but I can't figure out how to control the speed at all. I currently have it setup for its soft-switching mode. I don't have experience with brushless motors and was hoping someone could point out what I am missing.
This link may help you : http://www.atmel.com/images/doc8012.pdf
You need a microcontroller to generate a PWM command to your controller:
Each PWM high and low phase signal is controlled by a microcontroller (enable signals Figure 5) which are the inputs U+/U- V+/V- and W+/W- in the HA13535. The outputs U, V and W are connected to the motor. Be sure that the motor is well adapted to the controller (current and voltage) and don't forget to add the flyback diodes.