mcf51ac256a Freescale Semiconductor, Inc, mcf51ac256a Datasheet - Page 382

• Manufacturer Part Number: mcf51ac256a
• Description: Mcf51ac Flexis
• Manufacturer: Freescale Semiconductor, Inc

Multipurpose Clock Generator (MCGV3)
16.4.2
Figure 16-9
16.4.3
The IREFS bit can be changed at anytime, but the actual switch to the newly selected clock is shown by
the IREFST bit. When switching between engaged internal and engaged external modes, the FLL or PLL
will begin locking again after the switch is completed.
16-14
Stop
Mode
MCG Mode State Diagram
Mode Switching
shows the MCG’s mode state diagram. The arrows indicate the permitted mode transitions.
—
Entered from any state when
the MCU enters Stop mode
MCF51AC256 ColdFire Integrated Microcontroller Reference Manual, Rev. 5
Related field values
Table 16-11. MCG Modes of Operation (continued)
BLPI
Figure 16-9. MCG Mode State Diagram
FEI
FBI
Entered whenever the MCU enters a Stop state. The FLL and PLL are
disabled, and all MCG clock signals are static except in the following
cases:
MCGIRCLK is active in Stop mode when all the following conditions
become true:
MCGERCLK is active in Stop mode when all the following conditions
become true:
• MCGC1[IRCLKEN] = 1
• MCGC1[IREFSTEN] = 1
• MCGC2[ERCLKEN] = 1
• MCGC2[EREFSTEN] = 1
Stop
FEE
FBE
PBE
PEE
Returns to the state that was active before
the MCU entered Stop mode, unless a
reset occurs while in Stop mode.
Description
BLPE
Freescale Semiconductor