AM29F032B_09 Datasheet, PDF (18/40 Pages) SPANSION – 32 Megabit (4 M x 8-Bit) CMOS 5.0 Volt-only, Uniform Sector Flash Memory

DATA SHEET
minates the time-out period and suspends the erase
operation.
After the erase operation has been suspended, the
system can read array data from or program data to
any sector not selected for erasure. (The device “erase
suspends” all sectors selected for erasure.) Normal
read and write timings and command definitions apply.
Reading at any address within erase-suspended sec-
tors produces status data on DQ7–DQ0. The system
can use DQ7, or DQ6 and DQ2 together, to determine
if a sector is actively erasing or is erase-suspended.
The Erase Resume command is valid only during the
Erase Suspend mode. See “Erase Suspend/Erase Re-
sume Commands” on page 15 for information on these
status bits.
After an erase-suspended program operation is com-
plete, the system can once again read array data within
non-suspended sectors. The system can determine
the status of the program operation using the DQ7 or
DQ6 status bits, just as in the standard program oper-
ation. See “Erase Suspend/Erase Resume Com-
mands” on page 15 for more information.
The system may also write the autoselect command
sequence when the device is in the Erase Suspend
mode. The device allows reading autoselect codes
even at addresses within erasing sectors, since the
codes are not stored in the memory array. When the
device exits the autoselect mode, the device reverts to
the Erase Suspend mode, and is ready for another
valid operation. See “Autoselect Command Sequence”
on page 14 for more information.
The system must write the Erase Resume command
(address bits are “don’t care”) to exit the erase suspend
mode and continue the sector erase operation. Further
writes of the Resume command are ignored. Another
Erase Suspend command can be written after the de-
vice has resumed erasing.
START
Write Erase
Command Sequence
Data Poll
from System
No
Data = FFh?
Embedded
Erase
algorithm
in progress
Yes
Erasure Completed
Notes:
1. See the appropriate Command Definitions table for erase
command sequence.
2. See “DQ3: Sector Erase Timer” for more information.
Figure 3. Erase Operation
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Am29F032B
21610D8 November 11, 2009