29.14.1 CPU Clock Switching Timings

The glitch-free clock switcher implemented to control the sources of CPU_CLK and MCK performs clock switching in 5 clock cycles of the currently used clock plus 5 cycles of the target clock.

The clock switching is effective once MCKRDY rises. See the following figure.

Figure 29-5. Switch CPU Clock (CPU_CLK) from Source Clock to Destination Clock