The invention discloses a general purpose interface controller, including a slave interface controller and a master interface controller, used to exchange data among master devices and slave devices in an electronic device. The slave interface controller receives data and a first control signal from one of the master devices, and converts the first control signal to a request signal. The master interface controller receives the data and the request signal from the slave interface controller, converts the request signal to a second control signal recognized by at least one of the slave devices, and forwards the data and the second control signal to the slave device.