A drive motor assembly for a power driven wheelchair comprises: a stator housing for containing field coils of a stator of the motor assembly; at least one sensor disposed in the stator housing for sensing rotation of the motor; a memory storing motor error parameter data including data of errors of the at least one sensor, the memory being embedded in the stator housing; and a connection for accessing the error parameter data of the memory from the stator housing. The motor error parameter data may be accessed from the embedded memory of the drive motor by a programmed motor controller for use in controlling the drive motor. Also, the motor error parameter data may be embedded in the drive motor by the steps of: controlling the motor through at least one predetermined drive pattern; sensing motor rotation during the drive pattern and generating signals representative thereof; deriving error parameter data of the drive motor from the generated signals; programming a memory with the derived error parameter data; and embedding the memory in the drive motor.