Security - NXP Semiconductors MKL27Z128VFM4 Reference Manual

45.4.10.13 Erase All Blocks Unsecure Command
The Erase All Blocks Unsecure operation erases all flash memory, verifies all memory
contents, programs the security byte in the Flash Configuration Field to the unsecure
state, and releases MCU security.
Table 45-33. Erase All Blocks Unsecure Command FCCOB Requirements
FCCOB Number
0
After clearing CCIF to launch the Erase All Blocks Unsecure command, the flash
memory module erases all program flash memory, then verifies that all are erased.
If the flash memory module verifies that all program flash memory was properly erased,
security is released by setting the FSEC[SEC] field to the unsecure state, and the security
byte (see Flash Configuration Field
the Erase All Blocks Unsecure command. If the erase or program verify fails, the
FSTAT[MGSTAT0] bit is set. The CCIF flag is set after the Erase All Blocks Unsecure
operation completes.
Table 45-34. Erase All Blocks Unsecure Command Error Handling
Error Condition
Command not available in current mode/security
Any errors have been encountered during erase or program verify operations

45.4.11 Security

The flash memory module provides security information to the MCU based on contents
of the FSEC security register.
The MCU then limits access to flash memory resources as defined in the device's Chip
Configuration details. During reset, the flash memory module initializes the FSEC
register using data read from the security byte of the Flash Configuration Field (see
Configuration Field
The following fields are available in the FSEC register. The settings are described in the
Flash Security Register (FTFA_FSEC)
Flash security features are discussed further in
Flash Protection Features
available on this device.
Freescale Semiconductor, Inc.
Description) is programmed to the unsecure state by
Description).
details.
. Note that not all features described in the application note are
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
Chapter 45 Flash Memory Module (FTFA)
FCCOB Contents [7:0]
0x49 (ERSALLU)
AN4507: Using the Kinetis Security and
Error Bit
FSTAT[ACCERR]
FSTAT[MGSTAT0]
Flash
927