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The per-task interrupt disable time is saved in the task’s OS_TCB during a context switch (see OSTaskSwHook() in os_cpu_c.c and described in Chapter 8, “Context Switching” Context Switching).
The unit of measure for the measured time is in CPU_TS (timestamp) units. It is necessary to find out the resolution of the timer used to measure these timestamps. For example, if the timer used for the timestamp is incremented at 1 MHz then the resolution of CPU_TS is 1 microsecond.
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