PXS20RM Datasheet, PDF (1092/1368 Pages) Freescale Semiconductor, Inc – PXS20 Microcontroller

Mode Entry Module (MC_ME)
NOTE
Software must ensure that the code executes from RAM before changing to
this mode if the flash is configured to be in the low-power or power-down
state in this mode.
32.4.2.5 RUN0…3 Modes
The device enters one of these modes on the following events:
• From the DRUN, SAFE, or another RUN0…3 mode when the TARGET_MODE bit field of the
ME_MCTL register is written with “0100…0111”
• From the HALT0 mode due to an interrupt event
• From the STOP0 mode due to an interrupt or wakeup event
As soon as any of the above events has occurred, a RUN0…3 mode transition request is generated. The
mode configuration information for these modes is provided by the ME_RUN0…3_MC registers. In these
modes, the flash, all clock sources, and the system clock configuration can be controlled by software as
required.
These modes are intended to be used by software
• To execute application routines
NOTE
Software must ensure that the code executes from RAM before changing to
this mode if the flash is configured to be in the low-power or power-down
state in this mode.
32.4.2.6 HALT0 Mode
The device enters this mode on the following events:
• From one of the RUN0…3 modes when the TARGET_MODE bit field of the ME_MCTL register
is written with “1000”.
As soon as any of the above events has occurred, a HALT0 mode transition request is generated. The mode
configuration information for this mode is provided by ME_HALT0_MC register. This mode is quite
configurable, and the ME_HALT0_MC register should be programmed according to the system needs.
The flash can be put in low-power or power-down mode as needed. If there is a HALT0 mode request while
an interrupt request is active, the transition to HALT0 is aborted with the resultant mode being the current
mode, SAFE (on SAFE mode request), or DRUN (on reset), and an invalid mode interrupt is not generated.
This mode is intended as a first-level low-power mode with
• The core clock frozen
• Only a few peripherals running
and to be used by software
• To wait until it is required to do something and then to react quickly (i.e. within a few system clock
cycles of an interrupt event)
32-36
PXS20 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor