Motorola MCF5282, MCF5281 Memory Map, Low-Power Interrupt Control Register Lpicr, Cwcr Lpicr Cwsr

Models: MCF5282 MCF5281

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Memory Map and Registers

7.2.2Memory Map

Table 7-1. Chip Configuration Module Memory Map

IPSBAR Offset

Bits 31–24

Bits 23–16

Bits 15–8

Bits 7–0

Access 1

0x0000_0010

Core Reset Status

Core Watchdog

Low-Power Interrupt

Core Watchdog

S

 

Register (CRSR) 2

Control Register

Control Register

Service Register

 

 

 

(CWCR)

(LPICR)

(CWSR)

 

 

 

 

 

 

 

0x0011_0004

Chip Configuration Register (CCR) 3

Reserved

Low-Power Control

S

 

 

 

 

Register (LPCR)

 

 

 

 

 

 

 

1S = CPU supervisor mode access only. User mode accesses to supervisor only addresses have no effect and result in a cycle termination transfer error.

2The CRSR, CWCR, and CWSR are described in the System Integration Module. They are shown here only to warn against accidental writes to these registers when accessing the LPICR.

3The CCR is described in the Chip Configuration Module. It is shown here only to warn against accidental writes to this register when accessing the LPCR.

7.2.3Register Descriptions

The following subsection describes the PMM registers.

7.2.3.1Low-Power Interrupt Control Register (LPICR)

Implementation of low-power stop mode and exit from a low-power mode via an interrupt require communication between the CPU and logic associated with the interrupt controller. The LPICR is an 8-bit register that enables entry into low-power stop mode, and includes the setting of the interrupt level needed to exit a low-power mode.

NOTE

The setting of the low-power mode select (LPMD) field in the power management module’s low-power control register (LPCR) determines which low-power mode the device enters when a STOP instruction is issued.

If this field is set to enter stop mode, then the ENBSTOP bit in the LPICR must also be set.

Following is the sequence of operations needed to enable this functionality:

1.The LPICR is programmed, setting the ENBSTOP bit (if stop mode is the desired low-power mode) and loading the appropriate interrupt priority level.

2.At the appropriate time, the processor executes the privileged STOP instruction. Once the processor has stopped execution, it asserts a specific Processor Status (PST) encoding. Issuing the STOP instruction when the LPICR[ENBSTOP] bit is set causes the SCM to enter stop mode.

7-2

MCF5282 User’s Manual

MOTOROLA

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Motorola MCF5282 Memory Map, Low-Power Interrupt Control Register Lpicr, Following subsection describes the PMM registers