The invention relates to a data communication system (100) and a method that can particularly be applied for communicating data from a medical instrument like a catheter or a guide-wire via a high-speedlink (101). The system (100) comprises (in-vivo) a slave component (150) with a controllable slave clock (153) and a transmitter (151) for transmitting a data signal (ds) that is clocked by the slave clock signal (clk). Moreover, it comprises (ex-vivo) a master component (110) with a clock controller (114,115,116) that receives a master clock signal (ref_clk) and the data signal (ds) and that generates a clock control signal (ccs) for adjusting the slave clock (153) to the master clock (113). The slave clock (153) may thus be realized with low space and energy requirements, e.g. by a voltage controlled oscillator (VCO). Moreover, the link (101) via which the data signal (ds) and the clock control signal (ccs) are exchanged may be realized by just two signal wires.