MC9S08SG8 Datasheet, PDF (49/310 Pages) Freescale Semiconductor, Inc – Microcontrollers

FLASH PROGRAM AND
ERASE FLOW
WRITE TO FCDIV (Note 1)
Chapter 4 Memory
Note 1: Required only once after reset.
START
0
FACCERR ?
1
CLEAR ERROR
WRITE TO FLASH
TO BUFFER ADDRESS AND DATA
WRITE COMMAND TO FCMD
WRITE 1 TO FCBEF
TO LAUNCH COMMAND
AND CLEAR FCBEF (Note 2)
Note 2: Wait at least four bus cycles
before checking FCBEF or FCCF.
FPVIOL OR
YES
FACCERR ?
NO
ERROR EXIT
0
FCCF ?
1
DONE
Figure 4-2. FLASH Program and Erase Flowchart
4.5.4 Burst Program Execution
The burst program command is used to program sequential bytes of data in less time than would be
required using the standard program command. This is possible because the high voltage to the FLASH
array does not need to be disabled between program operations. Ordinarily, when a program or erase
command is issued, an internal charge pump associated with the FLASH memory must be enabled to
supply high voltage to the array. Upon completion of the command, the charge pump is turned off. When
a burst program command is issued, the charge pump is enabled and then remains enabled after completion
of the burst program operation if these two conditions are met:
• The next burst program command has been queued before the current program operation has
completed.
• The next sequential address selects a byte on the same physical row as the current byte being
programmed. A row of FLASH memory consists of 64 bytes. A byte within a row is selected by
addresses A5 through A0. A new row begins when addresses A5 through A0 are all zero.
MC9S08SG8 MCU Series Data Sheet, Rev. 0
Freescale Semiconductor
PRELIMINARY
49