45.4.10.8 Read 1s All Blocks CommandThe Read 1s All Blocks command checks if the program flash blocks have been erased tothe specified read margin level, if applicable, and releases security if the readout passes,i.e. all data reads as '1'.Table 45-22. Read 1s All Blocks Command FCCOB RequirementsFCCOB Number FCCOB Contents [7:0]0 0x40 (RD1ALL)1 Read-1 Margin ChoiceAfter clearing CCIF to launch the Read 1s All Blocks command, the flash memorymodule :• sets the read margin for 1s according to Table 45-23,• checks the contents of the program flash are in the erased state.If the flash memory module confirms that these memory resources are erased, security isreleased by setting the FSEC[SEC] field to the unsecure state. The security byte in theflash configuration field (see Flash Configuration Field Description) remains unaffectedby the Read 1s All Blocks command. If the read fails, i.e. all memory resources are not inthe fully erased state, the FSTAT[MGSTAT0] bit is set.The CCIF flag sets after the Read 1s All Blocks operation has completed.Table 45-23. Margin Level Choices for Read 1s All BlocksRead Margin Choice Margin Level Description0x00 Use the 'normal' read level for 1s0x01 Apply the 'User' margin to the normal read-1 level0x02 Apply the 'Factory' margin to the normal read-1 levelTable 45-24. Read 1s All Blocks Command Error HandlingError Condition Error BitAn invalid margin choice is specified FSTAT[ACCERR]Read-1s fails FSTAT[MGSTAT0]Functional DescriptionKL27 Sub-Family Reference Manual , Rev. 5, 01/2016922 Freescale Semiconductor, Inc.
