Freescale Semiconductor HCS08 Series, Reference Manual

Page: 52 / 306

Chapter 4 Memory
MC9S08JS16 MCU Series Reference Manual, Rev. 4
52 Freescale Semiconductor
Figure 4-4. 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 is
completed.
START
WRITE COMMAND TO FCMD
NO
YES
FPVIOL OR
WRITE 1 TO FCBEF
TO LAUNCH COMMAND
AND CLEAR FCBEF
(2)
1
0
FCCF?
(3)
ERROR EXIT
DONE
(2)
Wait at least four bus cycles
before checking FCBEF or FCCF.
0
FACCERR OR FPVIOL?
CLEAR ERRORS
FACCERR?
WRITE TO FCDIV
(1) (1)
Required only once
after reset.
PROGRAM AND
ERASE FLOW
WRITE TO FLASH TO BUFFER
ADDRESS AND DATA
0
FCBEF?
(3)
During this time, avoid actions
that woudl result in an
FACCERR error.
Such as executing a
STOP instruction or writing
to the flash.
Reads of the flash during
program or erase are
ignored and invalid data
is returned.
1