(1) For applications using X1/X2 for OSCCLK, the user must characterize their
specific oscillator start-up time as it is dependent on circuit/layout external
to the device. See the Crystal Oscillator Electrical Characteristics
section for more information. For applications using INTOSC1 or INTOSC2 for
OSCCLK, see Section 6.8.3.5 for toscst. Oscillator start-up time does not
apply to applications using a single-ended crystal on the X1 pin, as it is
powered externally to the device.