5.4.3 Fail-Safe Condition Clearing

The Fail-Safe condition is cleared after a Reset, executing a SLEEP instruction or changing the NOSC and NDIV bits of the OSCCON1 register. When switching to the external oscillator or external oscillator with PLL, the OST is restarted. While the OST is running, the device continues to operate from the INTOSC selected in OSCCON1. When the OST times out, the Fail-Safe condition is cleared after successfully switching to the external clock source. The OSFIF bit must be cleared prior to switching to the external clock source. If the Fail-Safe condition still exists, the OSFIF flag will again be set by hardware.