The CoreSight 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). It is a TPIU-like device that supports a limited subset of the full TPIU functionality, to minimize gate count for a simple debug solution.
Compared to the 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 1. SWO Block Diagram
