ERSSUSP bit is set, the Erase Flash Sector operation is suspended and the flash memorymodule sets CCIF. While ERSSUSP is set, all writes to flash registers are ignored exceptfor writes to the FSTAT and FCNFG registers.If an Erase Flash Sector operation effectively completes before the flash memory moduledetects that a suspend request has been made, the flash memory module clears theERSSUSP bit prior to setting CCIF. When an Erase Flash Sector operation has beensuccessfully suspended, the flash memory module sets CCIF and leaves the ERSSUSP bitset. While CCIF is set, the ERSSUSP bit can only be cleared to prevent the withdrawal ofa suspend request before the flash memory module has acknowledged it.27.4.10.5.2 Resuming a Suspended Erase Flash Sector OperationIf the ERSSUSP bit is still set when CCIF is cleared to launch the next command, theprevious Erase Flash Sector operation resumes. The flash memory module acknowledgesthe request to resume a suspended operation by clearing the ERSSUSP bit. A newsuspend request can then be made by setting ERSSUSP. A single Erase Flash Sectoroperation can be suspended and resumed multiple times.There is a minimum elapsed time limit between the request to resume the Erase FlashSector operation (CCIF is cleared) and the request to suspend the operation again(ERSSUSP is set). This minimum time period is required to ensure that the Erase FlashSector operation will eventually complete. If the minimum period is continually violated,i.e. the suspend requests come repeatedly and too quickly, no forward progress is madeby the Erase Flash Sector algorithm. The resume/suspend sequence runs indefinitelywithout completing the erase.27.4.10.5.3 Aborting a Suspended Erase Flash Sector OperationThe user may choose to abort a suspended Erase Flash Sector operation by clearing theERSSUSP bit prior to clearing CCIF for the next command launch. When a suspendedoperation is aborted, the flash memory module starts the new command using the newFCCOB contents.NoteAborting the erase leaves the bitcells in an indeterminate,partially-erased state. Data in this sector is not reliable until anew erase command fully completes.The following figure shows how to suspend and resume the Erase Flash Sector operation.Chapter 27 Flash Memory Module (FTFA)KL04 Sub-Family Reference Manual, Rev. 3.1, November 2012Freescale Semiconductor, Inc. 407
