Motorola MCF5281, MCF5282 user manual Lpicr Field Description, Enbstop

Models: MCF5282 MCF5281

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Memory Map and Registers

3.The entry into a low-power mode is processed by the low-power mode control logic, and the appropriate clocks (usually those related to the high-speed processor core) are disabled.

4.After entering the low-power mode, the interrupt controller enables a combinational logic path which evaluates any unmasked interrupt requests. The device waits for an event to generate an interrupt request with a priority level greater than the value programmed in LPICR[XLPM_IPL[2:0]].

NOTE

Only fixed (external) interrupt can bring a device out of stop mode. To exit from other low-power modes, such as doze or wait, either fixed or programmable interrupts may be used; however, the module generating the interrupt must be enabled in that particular low-power mode.

5.Once an appropriately-high interrupt request level arrives, the interrupt controller signals its presence, and the SIM responds by asserting the request to exit low-power mode.

6.The low-power mode control logic senses the request signal and re-enables the appropriate clocks.

7.With the processor clocks enabled, the core processes the pending interrupt request.

 

 

7

6

 

 

 

4

 

3

0

 

 

Field

ENBSTOP

 

 

XLPM_IPL[2:0]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reset

1/0

 

0

 

1/0

 

0

 

 

Undefined

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

R/W

 

 

 

 

 

 

 

R/W

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Address

 

 

 

 

 

IPSBAR + 0x012

 

 

 

 

 

 

 

 

 

 

 

 

Figure 7-1. Low-Power Interrupt Control Register (LPICR)

 

 

 

 

Table 7-2. LPICR Field Description

 

 

 

 

 

 

 

 

 

 

 

 

 

Bits

Name

 

 

 

 

 

 

 

 

Description

 

 

 

 

 

 

 

 

 

 

 

7

ENBSTOP

 

Enable low-power stop mode.

 

 

 

 

 

 

 

 

0 Low-power stop mode disabled

 

 

 

 

 

 

 

 

1 Low-power stop mode enabled. Once the core is stopped and the signal to enter stop mode is

 

 

 

asserted, processor clocks can be disabled.

 

 

 

 

 

 

 

6–4

XLPM_IPL[2:0]

 

Exit low-power mode interrupt priority level. This field defines the interrupt priority level needed to

 

 

 

exit the low-power mode.Refer to Table 7-3.

 

 

 

 

 

 

 

 

 

 

 

 

3–0

 

Reserved, should be cleared.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

MOTOROLA

Chapter 7. Power Management

7-3

Page 171
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Motorola MCF5281, MCF5282 user manual Lpicr Field Description, Enbstop