The present invention provides a motor controller having one or more multi-functional pins. The motor controller includes a plurality of pins but does not include a dedicated pin for transmitting a clock signal and a dedicated pin for transmitting a motor specification database setting signal, wherein the clock signal and the motor specification database setting signal are for setting motor specification data. The clock signal and the motor specification database setting signal are transmitted through two of the plural pins which are multi-functional function pins shared by other functions in a normal operation mode. In a motor specification database setting mode, these multi-functional function pins are used for transmitting the clock signal and the motor specification database setting signal. In the normal operation mode, these multi-functional function pins are used for other functions.