MC9S12XD256MAL Datasheet, PDF (1134/1348 Pages) Freescale Semiconductor, Inc – Freescale’s Scalable Controller Area Network

Chapter 27 512 Kbyte Flash Module (S12XFTX512K4V2)
27.4.2.3 Program Command
The program operation will program a previously erased word in the Flash memory using an embedded
algorithm.
An example flow to execute the program operation is shown in Figure 27-28. The program command write
sequence is as follows:
1. Write to a Flash block address to start the command write sequence for the program command. The
data written will be programmed to the address written. Multiple Flash blocks can be
simultaneously programmed by writing to the same relative address in each Flash block.
2. Write the program command, 0x20, to the FCMD register.
3. Clear the CBEIF flag in the FSTAT register by writing a 1 to CBEIF to launch the program
command.
If a word to be programmed is in a protected area of the Flash block, the PVIOL flag in the FSTAT register
will set and the program command will not launch. Once the program command has successfully launched,
the CCIF flag in the FSTAT register will set after the program operation has completed unless a new
command write sequence has been buffered. By executing a new program command write sequence on
sequential words after the CBEIF flag in the FSTAT register has been set, up to 55% faster programming
time per word can be effectively achieved than by waiting for the CCIF flag to set after each program
operation.
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MC9S12XDP512 Data Sheet, Rev. 2.21
Freescale Semiconductor