LH28F800SG-L Datasheet, PDF (14/45 Pages) Sharp Electrionic Components – 8 M-bit (512 kB x 16) SmartVoltage Flash Memories

At this point, a Read Array command can be
written to read data from blocks other than that
which is suspended. A Word Write command
sequence can also be issued during erase suspend
to program data in other blocks. Using the Word
Write Suspend command (see Section 4.8), a
word write operation can also be suspended.
During a word write operation with block erase
suspended, status register bit SR.7 will return to "0"
and the RY/BY# output will transition to VOL.
However, SR.6 will remain "1" to indicate block
erase suspend status.
The only other valid commands while block erase is
suspended are Read Status Register and Block
Erase Resume. After a Block Erase Resume
command is written to the flash memory, the WSM
will continue the block erase process. Status
register bits SR.6 and SR.7 will automatically clear
and RY/BY# will return to VOL. After the Erase
Resume command is written, the device
automatically outputs status register data when
read (see Fig. 5). VPP must remain at VPPH1/2/3
(the same VPP level used for block erase) while
block erase is suspended. RP# must also remain at
VIH or VHH (the same RP# level used for block
erase). WP# must also remain at VIL or VIH (the
same WP# level used for block erase). Block erase
cannot resume until word write operations initiated
during block erase suspend have completed.
4.8 Word Write Suspend Command
The Word Write Suspend command allows word
write interruption to read data in other flash memory
locations. Once the word write process starts,
writing the Word Write Suspend command requests
that the WSM suspend the word write sequence at
a predetermined point in the algorithm. The device
continues to output status register data when read
after the Word Write Suspend command is written.
Polling status register bits SR.7 and SR.2 can
determine when the word write operation has been
suspended (both will be set to "1"). RY/BY# will
LH28F800SG-L/SGH-L (FOR TSOP, CSP)
also transition to VOH. Specification tWHRH1 defines
the word write suspend latency.
At this point, a Read Array command can be
written to read data from locations other than that
which is suspended. The only other valid
commands while word write is suspended are Read
Status Register and Word Write Resume. After
Word Write Resume command is written to the
flash memory, the WSM will continue the word
write process. Status register bits SR.2 and SR.7
will automatically clear and RY/BY# will return to
VOL. After the Word Write Resume command is
written, the device automatically outputs status
register data when read (see Fig. 6). VPP must
remain at VPPH1/2/3 (the same VPP level used for
word write) while in word write suspend mode. RP#
must also remain at VIH or VHH (the same RP#
level used for word write). WP# must also remain
at VIL or VIH (the same WP# level used for word
write).
4.9 Set Block and Permanent Lock-
Bit Commands
The combination of the software command
sequence and hardware WP#, RP# pin provides
most flexible block lock (write protection) capability.
The word write/block erase operation is restricted
by the status of block lock-bit, WP# pin, RP# pin
and permanent lock-bit. The status of WP# pin,
RP# pin and permanent lock-bit restricts the set
block bit. When the permanent lock-bit has not
been set, and when WP# = VIH or RP# = VHH, the
block lock bit can be set with the status of the RP#
pin. When RP# = VHH, the permanent lock-bit can
be set with the permanent lock-bit set command.
After the permanent lock-bit has been set, the
write/erase operation to the block lock-bit can never
be accepted. Refer to Table 5 for the hardware
and the software write protection.
Set block lock-bit and permanent lock-bit are
executed by a two-cycle command sequence. The
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