PXD10RM Datasheet, PDF (558/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

The Flash Module enters the read state on reset.
The Module is in the read state under two sets of conditions:
• The read state is active when the Module is enabled (User Mode Read)
• The read state is active when MCR.ERS and MCR.ESUS are high and MCR.PGM is low (Erase
Suspend).
Notice that no Read-While-Modify is available.
Flash Core reads return 128 bits (1 Page = 2 Double Words).
Registers reads return 32 bits (1 Word).
Flash Core reads are done through the Bus Interface Unit.
Registers reads to unmapped register address space will return all 0’s.
Registers writes to unmapped register address space will have no effect.
Array reads attempted to invalid locations will result in indeterminate data. Invalid locations occur when
addressing is done to blocks that do not exist in non 2ⁿ array sizes.
Interlock writes attempted to invalid locations, will result in an interlock occurring, but attempts to
program these blocks will not occur since they are forced to be locked. Erase will occur to selected and
unlocked blocks even if the interlock write is to an invalid location.
Simultaneous Read cycle on the Flash Matrix and Read/Write cycles on the Registers are possible. On the
contrary Registers Read/Write accesses simultaneous to a Flash Matrix interlock write are forbidden.
17.2.5.1 Reset
A reset is the highest priority operation for the Flash Module and terminates all other operations.
The Flash Module uses reset to initialize register and status bits to their default reset values.
If the Flash Module is executing a Program or Erase operation (MCR.PGM = 1 or MCR.ERS = 1) and a
reset is issued, the operation will be aborted and the module will disable the high voltage logic without
damage to the high voltage circuits. Reset aborts 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.
17.2.5.2 Power-Down Mode
The Power-Down mode turns off all Flash 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.
17-8
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
Freescale Semiconductor