The TMC implements a synchronisation request slave interface, SYNCREQS. This is an output signal that is asserted for one cycle periodically when trace capture is enabled, and this period is controlled by the Periodic Synchronization Counter Register (PSCR). It is normally left unconnected, but can be used to control the synchronization frequency of trace sources.

In ETF configuration, the TMC also implements a synchronisation request master interface, SYNCREQM. This is an input signal, and SYNCREQS is driven by this signal instead of the Periodic Synchronization Counter if pulses on SYNCREQM occur more frequently. It is normally tied LOW.