AM29SL800DB120WAC AMD [Advanced Micro Devices], AM29SL800DB120WAC Datasheet - Page 19

• Manufacturer Part Number: AM29SL800DB120WAC
• Description: 8 Megabit (1 M x 8-Bit/512 K x 16-Bit) CMOS 1.8 Volt-only Super Low Voltage Flash Memory
• Manufacturer: AMD [Advanced Micro Devices]

this time to ensure all commands are accepted. The
interrupts can be re-enabled after the last Sector Erase
command is written. If the time between additional
sector erase commands can be assumed to be less
than 50 µs, the system need not monitor DQ3. Any
command other than Sector Erase or Erase
Suspend during the time-out period resets the
device to reading array data. The system must
rewrite the command sequence and any additional
sector addresses and commands.
The system can monitor DQ3 to determine if the sector
erase timer has timed out. (See
Timer‚ on page
edge of the final WE# pulse in the command sequence.
Once the sector erase operation has begun, only the
Erase Suspend command is valid. All other commands
are ignored. Note that a hardware reset during the
sector erase operation immediately terminates the
operation. The Sector Erase command sequence
should be reinitiated once the device has returned to
reading array data, to ensure data integrity.
When the Embedded Erase algorithm is complete, the
device returns to reading array data and addresses are
no longer latched. The system can determine the
status of the erase operation by using DQ7, DQ6, DQ2,
or RY/BY#. (Refer to
page 20
Figure 4, on page 18
erase operation. Refer to the
parameters, and to
diagrams.
Erase Suspend/Erase Resume Commands
The Erase Suspend command allows the system to
interrupt a sector erase operation and then read data
from, or program data to, any sector not selected for
erasure. This command is valid only during the sector
erase operation, 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 operation or Embedded Program algo-
rithm. Writing the Erase Suspend command during the
Sector Erase time-out immediately terminates the
January 23, 2007 27546A6
for information on these status bits.)
22.) The time-out begins from the rising
Figure 18, on page 33
illustrates the algorithm for the
Write Operation Status‚ on
Table 16 on page
DQ3: Sector Erase
D A T A
for timing
39for
Am29SL800D
S H E E T
time-out period and suspends the erase operation.
Addresses are “don’t-cares” when writing the Erase
Suspend command.
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 sector erase time-out, the device immediately ter-
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
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-sus-
pended. See
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
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
on page 15
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
device has resumed erasing.
for more information.
Write Operation Status‚ on page 20
Write Operation Status‚ on page 20
Autoselect Command Sequence‚
for
for
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