Electronic device, electronic system and method therefor for automatically detecting and identifying peripheral device

The invention provides a method for an electronic device for automatically detecting and identifying a peripheral device. The electronic device comprises a connector having a first pin and a second pin and connects to a peripheral device through the connector. The method comprises the steps of determining whether the peripheral device is connected to the connector; reading a first state of the first pin and the second pin when determining that the peripheral device is connected to the connector; setting a voltage of the first pin to a first voltage level and then reading a second state of the first pin and the second pin; and identifying the peripheral device according to the first state and the second state. The invention also provides an electronic device and an electronic system utilizing the above-mentioned method.