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IAR Embedded Workbench for Arm 9.70.x

Getting started with SWO trace

In this section:

  1. Before you start C-SPY, choose Project>Option>Driver

    Click the Setup tab or the Connection tab, respectively, and choose Interface>SWD.

  2. After you have started C-SPY, choose SWO Trace Windows Settings from the C-SPY driver menu. In the dialog box that appears, make your settings for controlling the output in the Trace window.

    To see statistical trace data, select the option Force>PC samples, see SWO Trace Window Settings dialog box.

  3. To configure the hardware’s generation of trace data, click the SWO Configuration button available in the SWO Configuration dialog box. For more information, see SWO Configuration dialog box.

    Note specifically these settings:

    • The value of the CPU clock option must reflect the frequency of the CPU clock speed at which the application executes. Note also that the settings you make are preserved between debug sessions.

    • To decrease the amount of transmissions on the communication channel, you can disable the Timestamp option. Alternatively, set a lower rate for PC Sampling or use a higher SWO clock frequency.

  4. Open the SWO Trace window—available from the C-SPY driver menu—and click activateButton.pngthe Activate button to enable trace data collection.

  5. Start the execution. The Trace window is continuously updated with trace data. For more information about the window, see Trace window.