Patent ID: 7975075
Filing Date: 2011-07-05
Classification: H04B

Abstract:
1. A data communication system comprising: a main device; and an external module connected to the main device and communicating data with the main device, wherein the external module transmits its identification information to the main device before the external module and the main device communicate the data therebetween, and the main device receives the identification information from the external module, confirms its connection to the external module, and transmits an identification information confirmation signal to the external module, wherein if the external module fails to receive the identification information confirmation signal from the main device, the external module periodically requests the main device to transmit the identification information confirmation signal for a predetermined period of time, wherein the identification information comprises a type of the external module, and the state of the main device is controlled in conformity with the type of the external module based on the identification information, wherein the main device comprises a universal asynchronous receiver/transmitter (UART) port, the external module comprises a UART port, and the main device and the external module communicate data using UART serial communication, and wherein the main device recognizes the type of the external module using only transmit (Tx) and receive (Rx) pins of the UART port without using a separate detection pin of the UART port.