CHAPTER 16 FLASH MEMORYUser’s Manual U18172EJ2V0UD24416.8.8 Example of byte write operation in self programming modeAn example of the byte write operation in self programming mode is explained below.<1> Set 05H (byte write) to the flash program command register (FLCMD).<2> Set the number of block to which data is to be written, to flash address pointer H (FLAPH).<3> Set the address at which data is to be written, to flash address pointer L (FLAPL).<4> Set the data to be written, to the flash write buffer register (FLW).<5> Clear the flash status register (PFS).<6> Write ACH to the watchdog timer enable register (WDTE) (clear and restart the watchdog timer counter)Note.<7> Execute the HALT instruction then start self programming. (Execute an instruction immediately after theHALT instruction if self programming has been executed.)<8> Check if a self programming error has occurred using bit 1 (VCERR) and bit 2 (WEPRERR) of PFS.Abnormal → <9>Normal → <10><9> Byte write processing is abnormally terminated.<10> Byte write processing is normally terminated.Note This setting is not required when the watchdog timer is not used.Caution If a write results in failure, erase the block once and write to it again.
