mcf51jf128 Freescale Semiconductor, Inc, mcf51jf128 Datasheet - Page 359

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

Chapter 16
Low Leakage Wakeup Unit (LLWU)
16.1 Introduction
The LLWU module allows the user to select up to 16 external pin sources and up to 8
internal modules as a wakeup source from low-leakage power modes. The input sources
are described in the device's Chip Configuration details. Each of the available wakeup
sources can be individually enabled.
The RESET pin is an additional source for triggering an exit from low-leakage power
modes and causes the MCU to exit both LLS and VLLS through a reset flow. The
LLWU_RST[LLRSTE] bit must be set to allow an exit from low-leakage modes via the
RESET pin. On a device where the RESET pin is shared with other functions, the explicit
port mux control register must be set for the RESET pin before the RESET pin can be
used as a low-leakage reset source.
The LLWU module also includes three optional digital pin filters: two for the external
wakeup pins and one for the RESET pin.
16.1.1 Features
The LLWU module features include:
Freescale Semiconductor, Inc.
• Supports up to 16 external input pins and up to 8 internal modules with individual
• Input sources may be external pins or from internal peripherals capable of running in
• Each external pin wakeup input is programmable as falling edge, rising edge, or any
• Wakeup inputs are activated if enabled once MCU enters a low-leakage power mode
• Optional digital filters provided to qualify an external pin detect and RESET pin
enable bits
LLS or VLLS. See the Chip Configuration information for wakeup input sources for
this device.
change
detect.
MCF51JF128 Reference Manual, Rev. 2, 03/2011
Preliminary
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