Apparatus for motor synchronization

A DC electric motor comprising:

• a rotor capable of rotating at a rotational speed;
• rotor circuitry that controls the rotational speed of the rotor;
• an input to receive an external reference signal indicating a preset speed;
• a programmable element operatively coupled with the input and the rotor circuitry within the motor, the programmable element being capable of comparing the external reference signal with the rotational speed of the rotor, the programmable element controlling the rotor circuitry based upon the comparison of the external reference signal and the rotational speed of the rotor,
• wherein the programmable element is programmed to detect an error condition with the external reference signal, the programmable element setting the rotational speed of the rotor to a selected speed if the error condition is detected,
• the motor further comprising an internal clock producing an internal clock signal, the selected speed being based upon the internal clock signal.

A rotor circuit for controlling the speed of a rotor, the rotor being a part of a DC electric motor, the rotor circuit comprising:

• switching circuitry that, at least in part, controls the rotational speed of the rotor;
• an input for receiving an external reference signal indicating a preset speed;
• and
• a programmable element operatively coupled with the input and the switching circuitry, the programmable element comparing the speed of the rotor with the preset speed indicated in the reference signal, the programmable element controlling the switching circuitry based on the comparison of the preset speed and the speed of the rotor, the switching circuitry and programmable element being internal to the motor,
• wherein the programmable element is programmed to detect an error condition with the external reference signal, the progrmmable element setting the speed of the rotor to a selected speed if the error condition is detected,
• the motor further comprising an internal clock producing an internal clock signal, the selected speed being based upon the internal clock signal.