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March 10, 2005 S29JL032H_00A11
S29JL032H
39
Ad vance
Info rmat i o n
Write Operation Status
The device provides several bits to determine the status of a program or erase
operation: DQ2, DQ3, DQ5, DQ6, and DQ7.
Table 14 and the following subsec-
tions describe the function of these bits. DQ7 and DQ6 each offer a method for
determining whether a program or erase operation is complete or in progress.
The device also provides a hardware-based output signal, RY/BY#, to determine
whether an Embedded Program or Erase operation is in progress or has been
completed.
DQ7: Data# Polling
The Data# Polling bit, DQ7, indicates to the host system whether an Embedded
Program or Erase algorithm is in progress or completed, or whether a bank is in
Erase Suspend. Data# Polling is valid after the rising edge of the final WE# pulse
in the command sequence.
During the Embedded Program algorithm, the device outputs on DQ7 the com-
plement of the datum programmed to DQ7. This DQ7 status also applies to
programming during Erase Suspend. When the Embedded Program algorithm is
complete, the device outputs the datum programmed to DQ7. The system must
provide the program address to read valid status information on DQ7. If a pro-
gram address falls within a protected sector, Data# Polling on DQ7 is active for
approximately 1 s, then that bank returns to the read mode.
During the Embedded Erase algorithm, Data# Polling produces a “0” on DQ7.
When the Embedded Erase algorithm is complete, or if the bank enters the Erase
Suspend mode, Data# Polling produces a “1” on DQ7. The system must provide
an address within any of the sectors selected for erasure to read valid status in-
formation on DQ7.
After an erase command sequence is written, if all sectors selected for erasing
are protected, Data# Polling on DQ7 is active for approximately 100 s, then the
bank returns to the read mode. If not all selected sectors are protected, the Em-
bedded Erase algorithm erases the unprotected sectors, and ignores the selected
sectors that are protected. However, if the system reads DQ7 at an address within
a protected sector, the status may not be valid.
When the system detects DQ7 has changed from the complement to true data,
it can read valid data at DQ15–DQ0 (or DQ7–DQ0 for x8-only device) on the fol-
lowing read cycles. Just prior to the completion of an Embedded Program or Erase
operation, DQ7 may change asynchronously with DQ15–DQ8 (DQ7–DQ0 for x8-
only device) while Output Enable (OE#) is asserted low. That is, the device may
change from providing status information to valid data on DQ7. Depending on
when the system samples the DQ7 output, it may read the status or valid data.
Even if the device has completed the program or erase operation and DQ7 has
valid data, the data outputs on DQ15–DQ0 may be still invalid. Valid data on
DQ15–DQ0 (or DQ7–DQ0 for x8-only device) will appear on successive read
cycles.
Polling timing diagram.