D A T A S H E E T
When the Embedded Erase algorithm is complete, the
device from entering Burst Mode. To enter Burst Mode
either the Erase operation must be allowed to complete
normally, or it can be prematurely terminated by issuing
a Hardware Reset.
device returns to reading array data and addresses are
no longer latched. The system can determine the sta-
tus of the erase operation by using DQ7, DQ6, DQ2, or
RY/BY#. (Refer to “Write Operation Status” for informa-
tion on these status bits.)
Burst Mode
While in Burst Mode the Erase Suspend command is
ignored and the device continues to operate normally in
Burst Mode. If Erase Suspend operation is required,
then Burst Mode must be terminated and Asynchro-
nous Mode initiated.
Figure 6 illustrates the algorithm for the erase opera-
tion. Refer to the Erase/Program Operations tables in
the “AC Characteristics” section for parameters, and to
Figure 19 for timing diagrams.
General
This command is valid only during the sector erase op-
eration, including the 50 µs time-out period during the
sector erase command sequence. The Erase Suspend
command is ignored if written during the chip erase op-
eration or Embedded Program algorithm. Writing the
Erase Suspend command during the Sector Erase
time-out immediately terminates the time-out period
and suspends the erase operation. Addresses are
“don’t-cares” when writing the Erase Suspend com-
mand.
START
Write Erase
Command Sequence
Data Poll
from System
When the Erase Suspend command is written during a
sector erase operation, the device requires a maximum
of 20 µs to suspend the erase operation. However, when
the Erase Suspend command is written during the sec-
tor erase time-out, the device immediately terminates
the time-out period and suspends the erase operation.
Embedded
Erase
algorithm
in progress
No
Data = FFh?
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.
Note that burst read is not available when the device is
erase-suspended. Only asynchronous reads are al-
lowed. Reading at any address within erase-sus-
pended sectors 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. See “Write Operation Status” for informa-
tion on these status bits.
Yes
Erasure Completed
Notes:
1. See Table 8 for erase command sequence.
2. See “DQ3: Sector Erase Timer” for more information.
Figure 6. Erase Operation
Erase Suspend/Erase Resume Commands
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 “Write Operation Status” for more informa-
tion.
The Erase Suspend command allows the system to in-
terrupt a sector erase operation and then read data
from, or program data to, any sector not selected for
erasure. The Erase Suspend command has a different
effect depending on whether the Flash device is in
Asynchronous Mode or Burst Mode.
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
Asynchronous Mode
The Erase Suspend command is only valid when the
Flash device is in Asynchronous Mode. During Erase
Suspend operation Asynchronous read/program oper-
ations behave normally in non-erasing sectors. How-
ever, Erase Suspend operation prevents the Flash
July 8, 2005
Am29BL162C
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SPANSION [ SPANSION ]
