W19B(L)320ST/B
As the Embedded Erase algorithm is complete, the device returns to reading array data and
addresses are no longer latched. Please refer to the Write Operation Status section for information on
these status bits.
When the sector erase operation begins, only the Erase Suspend command is valid. All other
commands are ignored. However, a hardware reset shall terminate the erase operation immediately. If
this occurs, to ensure data integrity, the sector erase command sequence should be reinitiated once
the device has returned to reading array data.
6.2.9 Erase Suspend/Erase Resume Commands
The Erase Suspend command, B0h, 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, which includes the 50 µS time-out period during the sector erase
command sequence. If written during the chip erase operation or Embedded Program algorithm, the
Erase Suspend command is ignored.
As the Erase Suspend command is written during the sector erase operation, a maximum of 20 µs is
required to suspend the erase operation. However, while the Erase Suspend command is written
during the sector erase time-out, the device shall terminate the time-out period and suspends the
erase operation immediately.
The device enters into an erase-suspend-read mode after the erase operation has been suspended.
The system can read data from, or program data to, any sector not selected for erasure. (In device
“erase suspends” all sectors are selected for erasure.) The “reading at any address within erase-
suspended sectors produces status” information is on DQ0−DQ7. The system can use DQ7, or DQ6
and DQ2 together, to determine whether a sector is actively erasing or is erase-suspended. Please
refer to the Write Operation Status section for detail information on these status bits.
After an erase-suspended program operation is complete, the device returns to the erase-suspend-
read mode. Using the DQ7 or DQ6 status bits, the system can determine the status of the program
operation, just as in the standard Byte Program operation. Please refer to the Write Operation Status
section for more information.
In the erase-suspend-read mode, the autoselect command sequence also can be issued. Please refer to
the Autoselect Mode and Autoselect Command Sequence sections for details.
The Erase Resume command must be written to resume the sector erase operation. Further writes of the
Resume command are ignored. After the chip has resumed erasing, another Erase Suspend command can
be written.
6.3 Write Operation Status
The device provides several bits to determine the status of a program or erase operation: DQ2, DQ3,
DQ5, DQ6, and DQ7. Each of DQ7 and DQ6 provides a method for determining whether a program or
erase operation is complete or in progress. The device also offers a hardware-based output signal,
RY/#BY, to determine whether an Embedded Program or Erase operation is in progress or has been
completed.
6.3.1 DQ7: #Data Polling
The #Data Polling bit, DQ7, indicates whether an Embedded Program or Erase algorithm is in
progress or completed, or whether or not the device is in Erase Suspend. Data Polling is valid after
the rising edge of the final #WE pulse in the command sequence.
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