Information

• 0x04 (Progress Swap to COMPLETE State) - After verifying that the current swap
state is UPDATE-ERASED and that the flash address provided matches the one
stored in the IFR Swap Field, the swap indicator located within bits [15:0] of the
flash address in the currently active program flash block will be programmed to
0x0000. Before executing with this swap control code, the user must erase the non-
active swap indicator using the Erase Flash Block or Erase Flash Sector commands
and update the application code or data as needed. The non-active swap indicator will
be checked at the erase verify level and if the check fails, the current swap state will
be changed to UPDATE with ACCERR set.
• 0x08 (Report Swap System Status) - After verifying that the flash address provided
matches the one stored in the IFR Swap Field, the status of the swap system will be
reported as follows:
• FCCOB5 (Current Swap State) - indicates the current swap state based on the
status of the swap enable word and the swap indicators. If the MGSTAT0 flag is
set after command completion, the swap state returned was not successfully
transitioned from and the appropriate swap command code must be attempted
again. If the current swap state is UPDATE and the non-active swap indicator is
0xFFFF, the current swap state is changed to UPDATE-ERASED.
• FCCOB6 (Current Swap Block Status) - indicates which program flash block is
currently located at relative flash address 0x0_0000.
• FCCOB7 (Next Swap Block Status) - indicates which program flash block will
be located at relative flash address 0x0_0000 after the next reset of the FTFL
module.
NOTE
It is recommended that the user execute the Swap Control
command to report swap status (code 0x08) after any reset to
determine if issues with the swap system were detected during
the swap state determination procedure.
NOTE
It is recommended that the user write 0xFF to FCCOB5,
FCCOB6, and FCCOB7 since the Swap Control command will
not always return the swap state and status fields when an
ACCERR is detected.
The swap indicators are implicitly protected from being programmed during Program
Longword or Program Section command operations and are implicitly unprotected during
Swap Control command operations. The swap indicators are implicitly protected from
being erased during Erase Flash Block and Erase Flash Sector command operations
unless the swap indicator being erased is in the non-active program flash block and the
Flash Operation in Low-Power Modes
K20 Sub-Family Reference Manual, Rev. 6, Nov 2011
644 Freescale Semiconductor, Inc.