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5. If a flash sector is larger than half the FlexRAM, repeat steps 3 and 4 until the sector
is completely programmed.
6. To program additional flash sectors, repeat steps 2 through 4.
7. To restore EEPROM functionality, execute the Set FlexRAM Function command to
make the FlexRAM available as EEPROM.
28.4.11.9 Read 1s All Blocks Command
The Read 1s All Blocks command checks if the program flash blocks, data flash blocks,
EEPROM backup records, and data flash IFR have been erased to the specified read
margin level, if applicable, and releases security if the readout passes, i.e. all data reads as
'1'.
Table 28-55. Read 1s All Blocks Command FCCOB Requirements
FCCOB Number FCCOB Contents [7:0]
0 0x40 (RD1ALL)
1 Read-1 Margin Choice
After clearing CCIF to launch the Read 1s All Blocks command, the flash memory
module :
• sets the read margin for 1s according to Table 28-56,
• checks the contents of the program flash, data flash, EEPROM backup records, and
data flash IFR are in the erased state.
If the flash memory module confirms that these memory resources are erased, security is
released by setting the FSEC[SEC] field to the unsecure state. The security byte in the
flash configuration field (see Flash Configuration Field Description) remains unaffected
by the Read 1s All Blocks command. If the read fails, i.e. all memory resources are not in
the fully erased state, the FSTAT[MGSTAT0] bit is set.
The EEERDY and RAMRDY bits are clear during the Read 1s All Blocks operation and
are restored at the end of the Read 1s All Blocks operation.
The CCIF flag sets after the Read 1s All Blocks operation has completed.
Table 28-56. Margin Level Choices for Read 1s All Blocks
Read Margin Choice Margin Level Description
0x00 Use the 'normal' read level for 1s
0x01 Apply the 'User' margin to the normal read-1 level
0x02 Apply the 'Factory' margin to the normal read-1 level
Functional Description
K20 Sub-Family Reference Manual, Rev. 1.1, Dec 2012
630
Preliminary
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