Abstract: An improved decoding apparatus for a Manchester code receives an asynchronous Manchester code, synchronizes to a received clock signal, and decodes an output NRZ code and an output synchronous clock signal. A first decoding unit samples an asynchronous Manchester code by synchronizing the asynchronous Manchester code to a shift of a received clock signal to produce a synchronous Manchester code and a synchronous clock, and computes an NRZ code. A tolerance check unit receives the synchronous Manchester code and checks a tolerance with respect to a shift at a bit cell center of the synchronous Manchester code. A multiplexer unit receives the NRZ code and the synchronous clock signal and selectively outputs a multiplexed NRZ code and a multiplexed synchronous clock signal in accordance with a detection signal outputted from the tolerance check unit.

Abstract: The circuit and method for detecting data collisions in a communication network, the circuit including: a data transition detecting section for receiving Manchester encoded data signals RXD, and detecting a transition at the center of the bit cell of the encoded data signals, and outputting a transition detecting signal Z having a certain pulse width; a delayer for delaying received clock signals RXC having a certain cycle synchronized with the received data signals RXD, and outputting delayed clock signals DRXC; and a data collision detecting section turning to an active mode in accordance with a data receiving status signal CRS illustrating the receiving status of the received data signals, and shifting the status of output signals in accordance with the transition detecting signal Z upon clocking of the delayed clock signal DRXC.