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17 lines
869 B
Markdown
17 lines
869 B
Markdown
# xtimer_drift test application
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Make note of the PC clock when starting this test. Let it run for a while, and
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compare the printed time against the expected time from the PC clock. The
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difference is the RIOT timer drift, this is likely caused by either:
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- an inaccurate hardware timer, or
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- bugs in the software (xtimer or periph/timer)
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This test will run a periodic timer every `TEST_INTERVAL` microseconds (`TEST_HZ`).
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The current time will be printed once per second, along with the difference
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between the actual and expected `xtimer_now` value. The first output variable
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`drift`, represents the total offset since start between `xtimer_now` and the
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expected time. The second output variable `jitter`, represents the difference
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in drift from the last printout. Two other threads are also running only to
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cause CPU load with extra interrupts and context switches.
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