1.2.1 Calibrated 32.768 kHz RC Oscillator

This RC oscillator provides an approximate 32.768 kHz clock. A factory-calibrated value is written to the 32.768 kHz oscillator Calibration register during Reset to ensure that the oscillator is running within its specification. The Calibration register can also be written from software for runtime calibration of the oscillator frequency. The oscillator employs a built-in prescaler providing both a 32.768 kHz output and a 1.024 kHz output.