5.4.2 How SWO Works with ITM Trace

The CoreSight Serial Wire Output (SWO) is a trace data drain that acts as a bridge between the on-chip trace data to a data stream that is captured by a Trace Port Analyzer (TPA) which is the MPLAB ICD 5 In-Circuit Debugger.

Compared to the Trace Port Interface Unit (TPIU), the SWO contains:

  • no formatter.
  • no pattern generator.
  • an 8-bit ATB input.
  • no synchronous trace output, that is, no TRACEDATA, TRACECTL, or TRACECLK pins.
  • no support for flush, because this is not required.
  • no support for triggering.
  • no external inputs and outputs (EXTCTLIN and EXTCTLOUT are not implemented).
Figure 5-2. SWO Block Diagram