Data communication manner, the optical fiber cable or the UTP cable or

摘要

PROBLEM TO BE SOLVED: To realize 1394 communication (communication based on IEEE1394) by using an optical fiber cable, an UTP cable and an STP cable, etc. ;SOLUTION: In 1394 communication, communication is possible by the data rates of S100, S200, S400, S800, S1600 and S3200 and by speed more than that in the future. When 1394 communication is executed by the optical fiber cable, an unshield twisted pair(UTP) cable and a shield twisted pair(STP) cable, correspondence is executed to the plural data rates so that a bit which is not used in data transfer inside a data packet to be transmitted is arranged in a data stream concerning the low-speed data rate. The transmission of the data transmission rate is realized by transmitting a prescribed speed control symbol through the use of the data stream. An equivalent operation is realized by the transmission of the prescribed control symbol concerning a Tp bias signal.;COPYRIGHT: (C)1998,JPO