ZHCSDA7G July 2014 – February 2018 DRV10983
The motor operation speed is automatically updated in register MotorSpeed1 and MotorSpeed2 while the motor is spinning. MotorSpeed1 contains the 8 most significant bits and MotorSpeed2 contains the 8 least significant bits. The value is determined by the period for calculated BEMF zero crossings on phase U. The electrical speed of the motor is denoted as Velocity (Hz) and is calculated as shown in Equation 8.
As an example consider the following:
MotorSpeed1 = 0x01;
MotorSpeed2 = 0xFF;
Velocity = 512 (0x01FF) / 10 = 51 Hz
For a 4-pole motor, this translates to: