MC9S12XEP100MAG Datasheet, PDF (936/1324 Pages) Freescale Semiconductor, Inc – Reference Manual Covers MC9S12XE Family

Chapter 25 256 KByte Flash Module (S12XFTM256K2V1)
25.4.2.11 Unsecure Flash Command
The Unsecure Flash command will erase the entire P-Flash and D-Flash memory space and, if the erase is
successful, will release security.
Table 25-53. Unsecure Flash Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x0B
Not required
Upon clearing CCIF to launch the Unsecure Flash command, the Memory Controller will erase the entire
P-Flash and D-Flash memory space and verify that it is erased. If the Memory Controller verifies that the
entire Flash memory space was properly erased, security will be released. If the erase verify is not
successful, the Unsecure Flash operation sets MGSTAT1 and terminates without changing the security
state. During the execution of this command (CCIF=0) the user must not write to any Flash module
register. The CCIF flag is set after the Unsecure Flash operation has completed.
Table 25-54. Unsecure Flash Command Error Handling
Register
FSTAT
FERSTAT
Error Bit
ACCERR
FPVIOL
MGSTAT1
MGSTAT0
EPVIOLIF
Error Condition
Set if CCOBIX[2:0] != 000 at command launch
Set if a Load Data Field command sequence is currently active
Set if command not available in current mode (see Table 25-30)
Set if any area of the P-Flash memory is protected
Set if any errors have been encountered during the verify operation
Set if any non-correctable errors have been encountered during the verify
operation
Set if any area of the buffer RAM EEE partition is protected
25.4.2.12 Verify Backdoor Access Key Command
The Verify Backdoor Access Key command will only execute if it is enabled by the KEYEN bits in the
FSEC register (see Table 25-11). The Verify Backdoor Access Key command releases security if user-
supplied keys match those stored in the Flash security bytes of the Flash configuration field (see Table 25-
3). The Verify Backdoor Access Key command must not be executed from the Flash block containing the
backdoor comparison key to avoid code runaway.
Table 25-55. Verify Backdoor Access Key Command FCCOB Requirements
CCOBIX[2:0]
000
001
010
011
100
FCCOB Parameters
0x0C
Key 0
Key 1
Key 2
Key 3
Not required
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