NXP Semiconductors MC9S08QL4, Справочное руководство

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Chapter 4 Memory
MC9S08QL8 MCU Series Reference Manual, Rev. 1
NXP Semiconductors 47
• 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.
The first byte of a series of sequential bytes being programmed in burst mode will take the same amount
of time to program as a byte programmed in standard mode. Subsequent bytes will program in the burst
program time provided that the conditions above are met. In the case the next sequential address is the
beginning of a new row, the program time for that byte will be the standard time instead of the burst time.
This is because the high voltage to the array must be disabled and then enabled again. If a new burst
command has not been queued before the current command completes, then the charge pump will be
disabled and high voltage removed from the array.
Figure 4-3. Flash Burst Program Flowchart
1
0
FCBEF?
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)
NO
YES
NEW BURST COMMAND?
1
0
FCCF?
(3)
ERROR EXIT
DONE
(2)
Wait at least four bus cycles
before checking FCBEF or FCCF.
FACCERR?
WRITE TO FCDIV
(1)
(1)
Required only once
after reset.
BURST PROGRAM
FLOW
(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.
0
FACCERR OR FPVIOL?
CLEAR ERRORS
1