Keil Logo

Trace Configuration

The Trace dialog defines generation and capturing of trace events via the Serial Wire Trace Output (SWO) pin. ULINK2 delivers trace information in real-time to the host PC.


  • While the debugger is running the Status Bar indicates the trace capturing operation.

Cortex-M Target Driver Setup - Trace Tab

General settings define system clock frequency and overall trace capturing.

Core Clock
Specify the processor core clock frequency here. The debugger uses this value to calculate timings for trace capturing and displays (such as current and voltage for example), even when trace is disabled. It also configures the debug unit's trace capture UART device. It should be be set to the system clock frequency that your target application uses in active state. If your device's trace clock does not run as fast as the system core clock, specify a separate Trace Clock.
Trace Enable
Enable this option to capture trace via the SWO pin.
Trace Clock
Specify the trace clock frequency here, if it differs from the Core Clock.
Use Core Clock
Enable this option to use the core clock frequency for trace. If your trace clock differs, uncheck and enter the correct trace clock in the Trace Clock box.

The sections below determine the trace ports and the captured information:

  • Trace Port configures the channel used for capturing trace.
  • ITM Stimulus Ports activates various ports, which can be used from the program code, to obtain debugging or program-specific information.
  • Timestamps sends time information along with trace events.
  • PC Sampling enables PC information indicating the program location that triggered a trace event.
  • Trace Events report specific CPU events.


Related Knowledgebase Articles

  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.