27.4.5 Flash Reads and Ignored WritesThe flash memory module requires only the flash address to execute a flash memoryread.The MCU must not read from the flash memory while commands are running (asevidenced by CCIF=0) on that block. Read data cannot be guaranteed from a flash blockwhile any command is processing within that block. The block arbitration logic detectsany simultaneous access and reports this as a read collision error (see theFSTAT[RDCOLERR] bit).27.4.6 Read While Write (RWW)The following simultaneous accesses are not allowed:• Reading from program flash memory space while a flash command is active(CCIF=0).27.4.7 Flash Program and EraseAll flash functions except read require the user to setup and launch a flash commandthrough a series of peripheral bus writes. The user cannot initiate any further flashcommands until notified that the current command has completed. The flash commandstructure and operation are detailed in Flash Command Operations.27.4.8 Flash Command OperationsFlash command operations are typically used to modify flash memory contents. The nextsections describe:• The command write sequence used to set flash command parameters and launchexecution• A description of all flash commands availableChapter 27 Flash Memory Module (FTFA)KL25 Sub-Family Reference Manual, Rev. 3, September 2012Freescale Semiconductor, Inc. 435
