MC9S08DZ60CLH Datasheet, PDF (54/416 Pages) Freescale Semiconductor, Inc – MC9S08DZ60 Series Features

Chapter 4 Memory
NOTE
Before programming a particular byte in the Flash or EEPROM, the sector
in which that particular byte resides must be erased by a mass or sector erase
operation. Reprogramming bits in an already programmed byte without first
performing an erase operation may disturb data stored in the Flash or
EEPROM memory.
2. Write the command code for the desired command to FCMD. The six valid commands are blank
check (0x05), byte program (0x20), burst program (0x25), sector erase (0x40), mass erase¹ (0x41),
and sector erase abort (0x47). The command code is latched into the command buffer.
3. Write a 1 to the FCBEF bit in FSTAT to clear FCBEF and launch the command (including its
address and data information).
A partial command sequence can be aborted manually by writing a 0 to FCBEF any time after the
write to the memory array and before writing the 1 that clears FCBEF and launches the complete
command. Aborting a command in this way sets the FACCERR access error flag which must be
cleared before starting a new command.
A strictly monitored procedure must be obeyed or the command will not be accepted. This
minimizes the possibility of any unintended changes to the memory contents. The command
complete flag (FCCF) indicates when a command is complete. The command sequence must be
completed by clearing FCBEF to launch the command. Figure 4-2 is a flowchart for executing all
of the commands except for burst programming and sector erase abort.
4. Wait until the FCCF bit in FSTAT is set. As soon as FCCF= 1, the operation has completed
successfully.
1. A mass erase is possible only when the Flash block is fully unprotected.
MC9S08DZ60 Series Data Sheet, Rev. 4
54
Freescale Semiconductor