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Internal RC oscillator calibration

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2.3.3

MSI calibration with fixed error

The MSI_CalibrateFixedError() function is provided to calibrate the MSI oscillator with

a maximum allowed frequency error in minimum time (by avoiding scan of all 256 trimming

values). The allowed error is configured by the user as an absolute value given in Hertz (the

first parameter: MaxAllowedError). This function is the same as

HSI16_CalibrateFixedError()

(refer to Section 2.3.1: HSI16/MSI calibration with

minimum error), with the exception that it calibrates the MSI oscillator using a binary search

algorithm.

The flowchart in Figure 11 provides the algorithm for this function.