Patent ID: 7286616

Claim:
A system in which data is transmitted between a transmitting device and a receiving device by transmitting a differential signal by using two transmission lines having a polarity, the transmitting device being operable to generate a differential transmission signal including a polarity decision signal whose signal level is constant for a length including a predetermined number of pieces of symbol data and sending the differential transmission signal to the transmission lines, the receiving device including: a connector section removably connected to the two transmission lines for receiving the differential transmission signal transmitted from the transmitting device when being connected to the transmission lines; a timing correcting section operable to correct a detection timing when the detection timing for detecting a signal level at a symbol position in the differential transmission signal, is successively incorrect for a plurality of symbol data whose number is larger than the number of pieces of symbol data representing the polarity decision signal; a polarity deciding section operable to detect the polarity decision signal included in the differential transmission signal received by the connector section and to decide, based on a signal level of the polarity decision signal, whether a connecting relationship of the connector section with the transmission lines has a positive polarity or a reversed polarity; and a signal processing section operable to handle the differential transmission signal received by the connector section as a signal having a normal polarity and perform a predetermined process when it is decided that the connecting relationship of the connector section with the transmission lines has the positive polarity, and operable to handle the differential transmission signal received by the connector section as a signal having a reversed polarity and perform the predetermined process when it is decided that the connecting relationship of the connector section with the transmission lines has the reversed polarity.