8.2.2.3 2x PLL

The oscillator module contains a PLL that can be used with the HFINTOSC clock source to provide a system clock source. The input frequency to the PLL is limited to 8, 12, or 16 MHz, which will yield a system clock source of 16, 24, or 32 MHz, respectively.

The PLL may be enabled for use by one of two methods:
  1. Program the RSTOSC bits in the Configuration Word 1 to ‘001’ to enable the HFINTOSC (32 MHz). This setting configures the HFFRQ bits to ‘101’ (16 MHz) and activates the 2x PLL.
  2. Write ‘001’ the NOSC bits to enable the 2x PLL, and write the correct value into the HFFRQ to select the desired system clock frequency.