Stable
Off
OSCCLK
CNT_DONE_4096
Start-Up
OSCCLK requested
External Clock Mode
Oscillator ON, Stable
Oscillator OFF
Oscillator ON, not yet stable
Oscillator ON
OSC_CLK_OUT = Static
OSC_CLK_OUT = Static
OSC_CLK_OUT = EXTAL
OSC_CLK_OUT = XTL_CLK
not requested
&&
Select OSC internal clock
OSCCLK requested
&&
Select clock from EXTAL signal
Figure 26-8. OSC Module state diagram
NOTE
XTL_CLK is the clock generated internally from OSC circuits.
26.8.1.1 Off
The OSC enters the Off state when the system does not require OSC clocks. Upon
entering this state, XTL_CLK is static unless OSC is configured to select the clock from
the EXTAL pad by clearing the external reference clock selection bit. For details
regarding the external reference clock source in this MCU, refer to the chip configuration
details. The EXTAL and XTAL pins are also decoupled from all other oscillator circuitry
in this state. The OSC module circuitry is configured to draw minimal current.
Functional Description
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
576
Freescale Semiconductor, Inc.