NXP Semiconductors MC9S08LG16, Reference Manual

Page: 63 / 373

Chapter 4 Memory
MC9S08LG32 MCU Series, Rev. 5
Freescale Semiconductor 63
Figure 4-2. Flash Program and Erase Flowchart
4.6.4 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.
START
WRITE TO FLASH
TO BUFFER ADDRESS AND DATA
WRITE COMMAND TO FCMD
NO
YES
FPVIOL OR
WRITE 1 TO FCBEF
TO LAUNCH COMMAND
AND CLEAR FCBEF
(2)
1
0
FCCF?
ERROR EXIT
DONE
(2)
Wait at least four bus cycles
0
FACCERR?
CLEAR ERROR
FACCERR?
WRITE TO FCDIV
(1)
(1)
Required only once after reset.
1
before checking FCBEF or FCCF.
FLASH PROGRAM AND
ERASE FLOW