PXD10RM Datasheet, PDF (909/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

25.1.2 Features
The MC_ME includes the following features:
• control of the available modes by the ME_ME register
• definition of various device mode configurations by the ME_<mode>_MC registers
• control of the actual device mode by the ME_MCTL register
• capture of the current mode and various resource status within the contents of the ME_GS register
• optional generation of various mode transition interrupts
• status bits for each cause of invalid mode transitions
• peripheral clock gating control based on the ME_RUN_PC0…7, ME_LP_PC0…7, and
ME_PCTL0…143 registers
• capture of current peripheral clock gated/enabled status
25.1.3 Modes of Operation
The MC_ME is based on several device modes corresponding to different usage models of the device.
Each mode is configurable and can define a policy for energy and processing power management to fit
particular system requirements. An application can easily switch from one mode to another depending on
the current needs of the system. The operating modes controlled by the MC_ME are divided into system
and user modes. The system modes are modes such as RESET, DRUN, SAFE, and TEST. These modes
aim to ease the configuration and monitoring of the system. The user modes are modes such as RUN0…3,
HALT, STOP, and STANDBY which can be configured to meet the application requirements in terms of
energy management and available processing power. The modes DRUN, SAFE, TEST, and RUN0…3 are
the device software running modes.
Table 25-1 describes the MC_ME modes.
Table 25-1. MC_ME Mode Descriptions
Name
Description
Entry
Exit
RESET
DRUN
SAFE
This is a chip-wide virtual mode during which the application is
not active. The system remains in this mode until all resources
are available for the embedded software to take control of the
device. It manages hardware initialization of chip configuration,
voltage regulators, oscillators, PLLs, and flash modules.
system reset
assertion from
MC_RGM
system reset
deassertion from
MC_RGM
This is the entry mode for the embedded software. It provides full
accessibility to the system and enables the configuration of the
system at startup. It provides the unique gate to enter USER
modes. BAM when present is executed in DRUN mode.
system reset
deassertion from
MC_RGM, software
request from SAFE,
TEST and RUN0…3,
wakeup request from
STANDBY
system reset
assertion, RUN0…3,
TEST, STANDBY via
software, SAFE via
software or hardware
failure.
This is a chip-wide service mode which may be entered on the
detection of a recoverable error. It forces the system into a
pre-defined safe configuration from which the system may try to
recover.
hardware failure,
software request
from DRUN, TEST,
and RUN0…3
system reset
assertion, DRUN via
software
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
25-3