Interface for controlling the phase alignment of clock signals for a recipient device

Abstract

Interface circuitry transmitting transactions between an initiator and a recipient includes: a clock input receiving a clock signal; a transaction input receiving transactions; clock outputs for outputting the clock signal; transaction outputs outputting the transactions to the recipient; and synchronizing circuits clocked by the clock signal and transmitting the transactions to the transaction output in response to the clock signal. A controllable delay circuit is provided between the clock input and the synchronizing circuits. A further synchronizing circuit configured to provide a similar delay. Phase detection circuitry is arranged to detect alignment of the received clock signals. Calibration control circuitry adjusts a delay of the controllable delay circuit during calibration until the phase detection circuitry detects alignment. The calibration control circuitry controls the controllable delay circuit to generate a delay to the clock signal in dependence upon the delay that generated the alignment detected during calibration.