D at a
S hee t
(Adva nce
In for m ation)
7.7.3
Sector Erase
The sector erase function erases one or more sectors in the memory array. (See
and
The device does not require the system to preprogram prior to erase. The Embedded Erase
algorithm automatically programs and verifies the entire memory for an all zero data pattern prior to electrical
erase. After a successful sector erase, all locations within the erased sector contain FFFFh. The system is
not required to provide any controls or timings during these operations.
After the command sequence is written, a sector erase time-out of no less than 50 µs occurs. During the time-
out period, additional sector addresses and sector erase commands may be written. Loading the sector erase
buffer may be done in any sequence, and the number of sectors may be from one sector to all sectors. The
time between these additional cycles must be less than 50 µs. Any sector erase address and command
following the exceeded time-out (50µs) may or may not be accepted. Any command other than Sector Erase
or Erase Suspend during the time-out period resets that sector to the read mode. The system can monitor
DQ3 to determine if the sector erase timer has timed out (See
The time-out begins from the
rising edge of the final WE# pulse in the command sequence.
When the Embedded Erase algorithm is complete, the sector returns to reading array data and addresses are
no longer latched. The system can determine the status of the erase operation by reading DQ7 or DQ6/DQ2
in the erasing sector. Refer to
for information on these status bits.
Once the sector erase operation has begun, only the Erase Suspend command is valid. All other commands
are ignored. However, note that a hardware reset immediately terminates the erase operation. If that occurs,
the sector erase command sequence should be reinitiated once that sector has returned to reading array
data, to ensure the sector is properly erased.
The Unlock Bypass feature allows the host system to send program commands to the Flash device without
first writing unlock cycles within the command sequence. See
for details on the Unlock Bypass
function.
illustrates the algorithm for the erase operation. Refer to
for parameters and timing
diagrams.
Software Functions and Sample Code
Table 7.8
Sector Erase
(LLD Function = lld_SectorEraseCmd)
Cycle
1
2
3
4
5
6
Description
Unlock
Unlock
Setup Command
Unlock
Unlock
Sector Erase Command
Operation
Write
Write
Write
Write
Write
Write
Byte Address
Base + AAAh
Base + 555h
Base + AAAh
Base + AAAh
Base + 555h
Sector Address
Word Address
Base + 555h
Base + 2AAh
Base + 555h
Base + 555h
Base + 2AAh
Sector Address
Data
00AAh
0055h
0080h
00AAh
0055h
0030h
Unlimited additional sectors may be selected for erase; command(s) must be written within 50 µs.
The following is a C source code example of using the sector erase function. Refer to the
Spansion Low Level
Driver User’s Guide
www.spansion.com)
for general information on Spansion Flash memory
software development guidelines.
/* Example: Sector Erase Command *
/
*(
*(
*(
*(
*(
*(
(UINT16
(UINT16
(UINT16
(UINT16
(UINT16
(UINT16
*)base_addr + 0x555
*)base_addr + 0x2AA
*)base_addr + 0x555
*)base_addr + 0x555
*)base_addr + 0x2AA
*)sector_address )
)
)
)
)
)
=
=
=
=
=
=
0x00AA;
0x0055;
0x0080;
0x00AA;
0x0055;
0x0030;
/*
/*
/*
/*
/*
/*
write
write
write
write
write
write
unlock cycle 1
*/
unlock cycle 2
*/
setup command
*/
additional unlock cycle 1 */
additional unlock cycle 2 */
sector erase command
*/
November 21, 2006 S29GL-P_00_A3
S29GL-P MirrorBit
TM
Flash Family
25
SPANSION [ SPANSION ]
