EN29LV641H/L EN29LV640U
using DQ7, DQ6, or DQ2. Refer to “Write Operation Status” for information on these status bits.
Flowchart 4 illustrates the algorithm for the erase operation. Refer to the Erase/Program Operations
tables in the “AC Characteristics” section for parameters, and to the Sector Erase Operations Timing
diagram for timing waveforms.
Sector Erase Suspend / Resume Command
The Sector 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. The Sector Erase Suspend command is ignored if written
during the chip erase operation or Embedded Program algorithm. Addresses are don’t-cares when
writing the Sector Erase Suspend command.
When the Sector Erase Suspend command is written during a sector erase operation, the device
requires a maximum of 20 µs to suspend 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. Normal read and write timings and command definitions
apply. Please note that Autoselect command sequence can not be accepted during Sector
Erase Suspend.
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-suspended. See “Write Operation Status” for information on these status bits.
After an erase-suspended program operation is complete, 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 operation. See “Write Operation
Status” for more information. The Autoselect command is not supported during Sector Erase
Suspend Mode.
The system must write the Sector Erase Resume command (address bits are don’t-care) to exit the
sector erase suspend mode and continue the sector erase operation. Further writes of the Resume
command are ignored. Another Sector Erase Suspend command can be written after the device has
resumed erasing.
WRITE OPERATION STATUS
DQ7: DATA# Polling
The device provides DATA# polling on DQ7 to indicate the status of the embedded operations. The
DATA# Polling feature is active during the Programming, Sector Erase, Chip Erase, and Sector
Erase Suspend. (See Table 10)
When the embedded programming is in progress, an attempt to read the device will produce the
complement of the data written to DQ7. Upon the completion of the programming operation, an
attempt to read the device will produce the true data written to DQ7. DATA# polling is valid after the
rising edge of the fourth WE# or CE# pulse in the four-cycle sequence for program.
When the embedded Erase is in progress, an attempt to read the device will produce a “0” at the
DQ7 output. Upon the completion of the embedded Erase, the device will produce the “1” at the DQ7
output during the read cycles. For Chip Erase or Sector Erase, DATA# polling is valid after the rising
edge of the last WE# or CE# pulse in the six-cycle sequence.
DATA# Polling must be performed at any address within a sector that is being programmed or
erased and not a protected sector. Otherwise, DATA# polling may give an inaccurate result if the
address used is in a protected sector.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
©2005 Eon Silicon Solution, Inc., www.essi.com.tw
20
Rev. B, Issue Date: 2005/06/27
EON [ EON SILICON SOLUTION INC. ]
