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Power Management
8-10
Freescale Semiconductor
capability of producing interrupts may cause the CPU to exit the doze mode and return to run mode.
Peripherals that are stopped restart operation on exit from doze mode as defined for each peripheral.
8.3.3.4
Stop Mode
Stop mode affects the CPU in the same manner as the wait and doze modes, except that all clocks to the
system are stopped and the peripherals cease operation.
Stop mode must be entered in a controlled manner to ensure that any current operation is properly
terminated. When exiting stop mode, most peripherals retain their pre-stop status and resume operation.
The following subsections specify the operation of each module while in and when exiting low-power
modes.
NOTE
Entering stop mode disables the SDRAMC including the refresh counter. If
SDRAM is used, then code is required to ensure proper entry and exit from
stop mode. See
Chapter 18, “SDRAM Controller (SDRAMC),”
for more
information.
8.3.4
Peripheral Behavior in Low-Power Modes
8.3.4.1
ColdFire Core
The ColdFire core is disabled during any low-power mode. No recovery time is required when exiting any
low-power mode.
8.3.4.2
Internal SRAM
The SRAM is disabled during any low-power mode. No recovery time is required when exiting any
low-power mode.
8.3.4.3
Clock Module
In wait and doze modes, the clocks to the CPU and SRAM is stopped and the system clocks to the
peripherals are enabled. Each module may disable the module clocks locally at the module level or the
module clocks may be individually disabled by the PPMR registers (refer to
Power Management Registers (PPMHR0, PPMHR1, & PPMLR0)”
). In stop mode, all clocks to the system
are stopped.
There are several options for enabling or disabling the PLL or crystal oscillator in stop mode,
compromising between stop mode current and wakeup recovery time. The PLL can be disabled in stop
mode, but requires a wakeup period before it can relock. The oscillator can also be disabled during stop
mode, but requires a wakeup period to restart.
When the PLL is enabled in stop mode (LPCR[STPMD] = 00), the external FB_CLK signal can support
systems using FB_CLK as the clock source. See
Section 8.2.5, “Low-Power Control Register (LPCR),”
for more information about operating the PLL in stop mode.
MCF5329 Reference Manual, Rev 3
Summary of Contents for MCF5329
Page 106: ...ColdFire Core 3 32 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 148: ...Cache 5 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 154: ...Static RAM SRAM 6 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 184: ...Power Management 8 18 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 204: ...Reset Controller Module 10 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 220: ...System Control Module SCM 11 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 228: ...Crossbar Switch XBS 12 8 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 268: ...General Purpose I O Module 13 40 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 392: ...SDRAM Controller SDRAMC 18 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 436: ...Fast Ethernet Controller FEC 19 44 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 594: ...FlexCAN 23 30 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 678: ...Pulse Width Modulation PWM Module 26 22 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 684: ...Watchdog Timer Module 27 6 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 704: ...DMA Timers DTIM0 DTIM3 29 12 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 754: ...UART Modules 31 34 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 770: ...I2 C Interface 32 16 Freescale Semiconductor MCF5329 Reference Manual Rev 3...
Page 866: ...Debug Module 36 50 Freescale Semiconductor MCF5329 Reference Manual Rev 3...