This Data Sheet may be revised by subsequent versions

© 2003 Eon Silicon Solution, Inc.,

www.eonssi.com

or modifications due to changes in technical specifications.

11

EN29LV040A

Rev. E, Issue Date: 2011/10/27

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.

Erase Suspend / Resume Command

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. The Erase Suspend command is ignored if written during the chip erase operation or

Embedded Program algorithm. 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.

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-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 Erase Suspend Mode.

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.

WRITE OPERATION STATUS

DQ7: DATA Polling

The EN29LV040A provides DATA Polling on DQ7 to indicate to the host system the status of the

Erase, Chip Erase, Erase Suspend. (See Table 6)

When the embedded Programming is in progress, an attempt to read the device will produce the

complement of the data last written to DQ7. Upon the completion of the embedded Programming, an

attempt to read the device will produce the true data last written to DQ7.

For the embedded

cycle sequence.

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

pulse in the six-cycle sequence. For Sector Erase, DATA polling is valid after the last rising edge of

the sector erase WE or CE pulse.

DATA Polling must be performed at any address within a sector that is being programmed or erased

is in a protected sector.

Just prior to the completion of the embedded operations, DQ7 may change asynchronously when the