Internal RC oscillator calibration

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Figure 8. Internal oscillator calibration: finding the minimum frequency

1. If the system clock source is HSI16, the trimming bits have a 5-bit length and the number of steps is 32. If

the system clock source is MSI, the trimming bits have an 8-bit length and the number of steps is 256.

2. Frequency measurement is detailed in Section 2.3.5.