D a t a S h e e t
DQ3: Sector Erase Timer
After writing a sector erase command sequence, the system may read DQ3 to determine
whether or not erasure has begun. (The sector erase timer does not apply to the chip erase
command.) If additional sectors are selected for erasure, the entire time-out also applies after
each additional sector erase command. When the time-out period is complete, DQ3 switches
from a 0 to a 1. If the time between additional sector erase commands from the system can
be assumed to be less than 50 µs, the system need not monitor DQ3. See also Sector Erase
Command Sequence‚ on page 57.
After the sector erase command is written, the system should read the status of DQ7 (Data#
Polling) or DQ6 (Toggle Bit I) to ensure that the device has accepted the command sequence,
and then read DQ3. If DQ3 is 1, the Embedded Erase algorithm has begun; all further com-
mands (except Erase Suspend) are ignored until the erase operation is complete. If DQ3 is 0,
the device accepts additional sector erase commands. To ensure the command is accepted,
the system software should check the status of DQ3 prior to and following each subsequent
sector erase command. If DQ3 is high on the second status check, the last command might
not have been accepted.
Table 16 on page 72 shows the status of DQ3 relative to the other status bits.
DQ1: Write-to-Buffer Abort
DQ1 indicates whether a Write-to-Buffer operation was aborted. Under these conditions DQ1
produces a 1. The system must issue the Write-to-Buffer-Abort-Reset command sequence to
return the device to reading array data. See Write Buffer‚ on page 14 for more details.
Table 16. Write Operation Status
DQ7
DQ5
DQ2
Status
(Note 2)
DQ6
(Note 1)
DQ3
N/A
1
(Note 2)
DQ1
0
RY/BY#
Embedded Program Algorithm
Embedded Erase Algorithm
Program-Suspended
DQ7#
0
Toggle
Toggle
0
0
No toggle
Toggle
0
0
Standard
Mode
N/A
Invalid (not allowed)
Data
1
1
1
1
0
Program
Suspend
Mode
Program-
Suspend
Read
Sector
Non-Program
Suspended Sector
Erase-Suspended
Sector
1
No toggle
Toggle
0
N/A
Toggle
N/A
N/A
N/A
Erase-
Suspend
Read
Erase
Suspend
Mode
Non-Erase
Suspended Sector
Data
Erase-Suspend-Program
(Embedded Program)
DQ7#
0
N/A
Busy (Note 3)
Abort (Note 4)
DQ7#
DQ7#
Toggle
Toggle
0
0
N/A
N/A
N/A
N/A
0
1
0
0
Write-to-
Buffer
Notes:
1. DQ5 switches to 1 when an Embedded Program, Embedded Erase, or Write-to-Buffer operation has exceeded the
maximum timing limits. Refer to the section on DQ5 for more information.
2. DQ7 and DQ2 require a valid address when reading status information. Refer to the appropriate subsection for
further details.
3. The Data# Polling algorithm should be used to monitor the last loaded write-buffer address location.
4. DQ1 switches to 1 when the device has aborted the write-to-buffer operation
72
S29GL-N MirrorBit™ Flash Family
S29GL-N_00_B3 October 13, 2006