Abstract: A data transmission system, for interconnecting a number of relatively closely-spaced user nodes, e.g. data terminals in a computer system, uses a passive bus terminated at each end by resistive terminations (T), which bus interconnects a number of system nodes (N). The nodes are identical and there is no central control to the system. To maintain synchronism between the nodes, there is a clock/sync. pulse circuit (CSS) connected to the mid-point of the bus. This enables the use of a bit rate of twice what would be possible if the source were connected to one end of the bus due to the reduced clock pulse skew effect.