Freescale Semiconductor MCF51QE128RM manual Burst Program Command

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Chapter 4 Memory

4.5.2.3Burst Program Command

The burst program operation programs previously erased data in the flash memory using an embedded algorithm.

While burst programming, two internal data registers operate as a buffer and a register (2-stage FIFO) so that a second burst programming command along with the necessary data can be stored to the buffers while the first burst programming command remains in progress. This pipelined operation allows a time optimization when programming more than one consecutive address on a specific row in the flash array as the high voltage generation can be kept active in between two programming commands.

An example flow to execute the burst program operation is shown in Figure 4-12. The burst program command write sequence is as follows:

1.Write to an aligned flash block address to start the command write sequence for the burst program command. The data written is programmed to the address written.

2.Write the program burst command, 0x25, to the FCMD register.

3.Clear the FCBEF flag in the FSTAT register by writing a 1 to FCBEF to launch the program burst command.

4.After the FCBEF flag in the FSTAT register returns to a 1, repeat steps 1 through 3. The address written is ignored but is incremented internally.

The burst program procedure can be used to program the entire flash memory even while crossing row boundaries within the flash array. If data to be burst programmed falls within a protected area of the flash array, FSTAT[FPVIOL] is set and the burst program command does not launch. After the burst program command has successfully launched and the burst program operation has completed, FSTAT[FCCF] is set unless a new burst program command write sequence has been buffered. By executing a new burst program command write sequence on sequential addresses after the FCBEF flag in the FSTAT register has been set, a greater than 50% faster programming time for the entire flash array can be effectively achieved when compared to using the basic program command.

MCF51QE128 MCU Series Reference Manual, Rev. 3

Freescale Semiconductor

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Freescale Semiconductor MCF51QE128RM manual Burst Program Command