PXD10RM Datasheet, PDF (603/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

damage to the high voltage circuits. Reset terminates all operations and forces the Flash Module into User
Mode ready to receive accesses. Reset and power-off must not be used systematically to terminate a
Program or Erase operation.
After reset is negated, read register access may be done, although it should be noted that registers that
require updating from shadow information, or other inputs, may not read updated values until
MCR.DONE transitions. MCR.DONE may be polled to determine if the Flash Module has transitioned
out of reset. Notice that the registers cannot be written until MCR.DONE is high.
17.3.5.2 Power-Down Mode
The Power-Down Mode turns off all flash memory DC current sources, so that power dissipation is due
only to leakage.
In Power-Down Mode no reads from or write to the Module are possible.
The user may not read some registers (UMISR0-4, UT1-2 and part of UT0) until the Disable Mode is
exited. On the contrary write access is locked on all the registers in Power-Down Mode.
When enabled the Flash Module returns to its previous state in all cases unless in the process of executing
an erase high voltage operation at the time of entering Power-Down Mode.
If the flash memory module enters Power-Down Mode during an erase operation, the MCR[ESUS] bit is
set. The user may resume the erase operation when the module exits Power-Down Mode by clearing the
MCR[ESUS] bit. MCR[EHV] must be high to resume the erase operation.
If the flash memory module is configured to enter Power-Down Mode during a program operation, the
operation will be completed and the Power-Down Mode will be entered only after the programming ends.
If the flash memory module is put in Power-Down Mode and the Vector Table remains mapped in the Flash
Address space, the user must take care that the Flash Macrocell will strongly increase the interrupt
response time by adding several Wait States.
It is forbidden to enter Low Power Mode when the Power-Down Mode is active.
17.3.5.3 Low Power Mode
The Low Power Mode turns off most of the DC current sources within the flash memory module.
The Module (Flash Core and Registers) is not accessible for read or write after it enters Low Power Mode.
The wake-up time from Low Power Mode is faster than the wake-up time from Power-Down Mode.
The user may not read some registers (UMISR0-4, UT1-2 and part of UT0) until the Low Power Mode is
exited. Write access is locked on all the registers in Low Power Mode.
When exiting from Low Power Mode the flash memory module returns to its previous state in all cases
unless it was in the process of executing an erase high voltage operation at the time of entering Low Power
Mode.
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
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