Freescale Semiconductor MCF51QE128RM manual FLL Bypassed External Low-Power Fbelp, Stop Stop

Models: MCF51QE128RM

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Chapter 1 Device Overview

 

 

IREFS=1

 

CLKS=00

 

LP=0

IREFS=0

FLL Engaged

Internal (FEI)

CLKS=10

 

LP=0

 

FLL Bypassed

 

FLL Bypassed

 

IREFS=1

CLKS=01

LP=0

FLL Bypassed

FLL Bypassed

External Low-

 

External (FBE)

 

Power(FBELP)

 

 

 

IREFS=0

CLKS=10 LP=1

FLL Engaged

External (FEE)

IREFS=0

CLKS=00

LP=0

Internal (FBI)

Internal Low- Power(FBILP)

IREFS=1

CLKS=01

LP=1

Entered from any state when

MCU enters stop with Stop ENBDM=0.

Returns to state that was active before MCU entered stop, unless reset occurs while in stop.

Figure 1-4. ICS Modes of Operation

1.4.3.6FLL Bypassed External Low-Power (FBELP)

In FLL bypassed external low-power mode, the FLLs are disabled and bypassed, and the ICS supplies a clock derived from the external reference clock. The external reference clock can be an external crystal/resonator supplied by an OSC controlled by the ICS, or it can be another external clock source.

1.4.3.7Stop (STOP)

In stop mode, the FLLs are disabled and the internal or external reference clocks can be selected to be enabled or disabled. The ICS does not provide an MCU clock source unless the debug ENBDM bit is set.

MCF51QE128 MCU Series Reference Manual, Rev. 3

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Freescale Semiconductor MCF51QE128RM manual FLL Bypassed External Low-Power Fbelp, Stop Stop