Abstract: Circuitry for synchronizing communications between clock environments wherein a change of state is transmitted from a first clock environment to a second clock environment, the first clock environment being timed by a first clock signal and the second clock environment being timed by a second clock signal, the first and second clock signals having nominally the same frequency but an unknown phase relationship, the circuitry comprising: delay means in the first clock environment arranged to generate a plurality of timing signals by delaying said first clock signal by respectively different delay values; sampling means in the second clock environment for sampling said plurality of timing signals at timing determined by said second clock signal thereby generating a plurality of sampled timing signals; and determining means for generating a control signal based on said plurality of sampled timing signals and outputting said control signal for controlling the transfer time of said change of state.

Abstract: A routing block using a switch with a pulsed serial link. An input of a routing block is supplied with an information signal. The routing block has multiple outputs. The information signal includes a first edge and a second edge on a single line. The first and second edges are separated by a time period. One of the first and second edges represents information conveyed by the signal. The other one of the first and second edges provides timing information. The information signal controls the routing block to select one of the multiple outputs and the transferring the signal to said selected one of said multiple outputs. Depending on the number of bits of information transmitted in each pulse and the number of switches controlled by the control information, the decoded control data will include at least one bit outputted serially to a control signal generator block.

Abstract: A system for controlling communications between a host and a target, the system having a data input for receiving a data signal, a clock input for receiving a clock signal, an oversampling circuit for sampling a received data signal and generating a control signal to control processing of the received data signal based at least in part on samples of the received data signal.

Abstract: A system comprising a host, a target and connection means therebetween. The host has means for providing a clock signal, first output means for outputting said clock signal to said target via said connection means and second output means for outputting data to said target via said connection means, said data being clocked out by said clock signal, said target having first input means for receiving said clock signal from said host, second input means for receiving said data from said host and first output means for outputting data to said host via said connection means. The host further comprises input means for receiving said data from said target, and oversampling means for oversampling the received data from the target and controlling the clocking in of said data received from said target in dependence on said oversampling.