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Clock Measurement

In the Trace tab, you need to set the correct clock frequency of your target. The debugger uses this setting for calculating timing for trace capturing and other displays, such as current and voltage. While this should be known from the settings that are used in the application, sometimes this can go wrong, due to complex clock setup with multiple PLL dividers on-chip. ULINKplus automatically checks the clock frequency of the running target using a simple JTAG/SWD connection. The measured clock frequency is shown in the System Analyzer window.

System Analyzer ButtonOpen the System Analyzer from the toolbar or via the menu View - Analysis Windows - System Analyzer.

Clock measurement in the System Analyzer window

After the application properly programs the clocks, the correct core clock will be displayed.


  • The clock measurement feature works on Arm Cortex-M3, Cortex-M4, Cortex-M7, and Cortex-M33 devices only.
  • Make sure that the displayed clock matches the Core Clock setting on the Trace tab in the Options for Target dialog.
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