> ## Documentation Index
> Fetch the complete documentation index at: https://docs.prescaler.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# RTT, SWO and instruction trace

> Correlate instrumented execution with source and timing.

Correlate instrumented execution with source and timing.

## Before you start

Firmware instrumentation plus a backend/probe/device that supports the selected trace path.

## Workflow

Enable only the needed trace mechanism in Target Configuration. For SWO, supply the actual clock from the firmware configuration. Open the corresponding trace view and capture the failing interval.

## Interpret the result

RTT, SWO/ITM and instruction trace are different technologies. Probe visibility does not imply support. A guessed clock can make decoded timing meaningless.

For an unexplained result, preserve the source/configuration and observation together. Use [Diagnose a failure](/workflows/diagnose) to turn it into a reproducible investigation. Check [support boundaries](/reference/limitations) before assuming a vendor-specific operation is implemented.