Are there notes to ponder in switching the clock from chip oscillator?

Switch to the main clock from the on-chip oscillator clock under the following conditions:

1. The main clock is oscillating stably.
2. The CM06 bit is "1" (divide-by-8 mode).

In addition, the CM15 bit must be set to "1" (oscillation drive capability = High) until the main clock oscillates stably.