mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 169

• Manufacturer Part Number: mcf51jf128
• Description: Mcf51jf128 Reference Manual
• Manufacturer: Freescale Semiconductor, Inc

Chapter 7
Power Management
7.1 Introduction
This chapter describes the various MCU power modes and functionality of the individual
modules in these modes.
7.2 Power modes
The V1 ColdFire CPU has two primary modes of operation, run and stop. The STOP
instruction can invoke both stop and wait modes. The CPU does not differentiate between
stop and wait modes. Stop, wait, and run are augmented in a number of ways to provide a
lower power MCU based on application needs.
The
multiple power options. The Very Low Power Run (VLPR) operating mode can reduce
runtime power when maximum processor frequency is not required. Corresponding wait
and stop modes are the Very Low Power Wait (VLPW) and Very Low Power Stop
(VLPS) modes.
Depending on the stop requirements of the user application, a variety of stop modes are
available that provide state retention, partial power down, or full power down of certain
logic and/or memory. I/O states are held in all modes of operation. The following table
compares the various power modes available.
Freescale Semiconductor, Inc.
Normal run
Normal wait
System Mode Controller (SMC)
Power mode
Allows maximum performance of MCU.
Allows peripherals to function while allowing CPU to sleep,
reducing power.
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Table 7-1. MCU power modes
Table continues on the next page...
module in ColdFire+ device families provides
Preliminary
Description
Interrupt
Normal recovery method
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