The High-Frequency Internal Oscillator (HFINTOSC) is a precision digitally-controlled internal clock source that produces a stable clock up to 64 MHz. The HFINTOSC can be enabled through one of the following methods:

The HFINTOSC frequency can be selected by setting the HFFRQ<3:0> bits.

The NDIV<3:0> bits allow for division of the HFINTOSC output from a range between 1:1 and 1:512.