EN29LV160B_11 Datasheet, PDF (19/43 Pages) Eon Silicon Solution Inc. – 16 Megabit (2048K x 8-bit / 1024K x 16-bit) Flash Memory Boot Sector Flash Memory, CMOS 3.0 Volt-only

Reading Toggle Bits DQ6/DQ2
EN29LV160B
Refer to Flowchart 6 for the following discussion. Whenever the system initially begins reading toggle
bit status, it must read DQ7–DQ0 at least twice in a row to determine whether a toggle bit is toggling.
Typically, a system would note and store the value of the toggle bit after the first read. After the second
read, the system would compare the new value of the toggle bit with the first. If the toggle bit is not
toggling, the device has completed the program or erase operation. The system can read array data on
DQ7–DQ0 on the following read cycle.
However, if after the initial two read cycles, the system determines that the toggle bit is still toggling, the
system also should note whether the value of DQ5 is high (see the section on DQ5). If it is, the system
should then determine again whether the toggle bit is toggling, since the toggle bit may have stopped
toggling just as DQ5 went high. If the toggle bit is no longer toggling, the device has successfully
completed the program or erase operation. If it is still toggling, the device did not complete the
operation successfully, and the system must write the reset command to return to reading array data.
The remaining scenario is that the system initially determines that the toggle bit is toggling and DQ5
has not gone high. The system may continue to monitor the toggle bit and DQ5 through successive
read cycles, determining the status as described in the previous paragraph. Alternatively, it may choose
to perform other system tasks. In this case, the system must start at the beginning of the algorithm
when it returns to determine the status of the operation (top of Flowchart 6).
Write Operation Status
Operation
Standar
d Mode
Erase
Suspend
Mode
Embedded Program
Algorithm
Embedded Erase Algorithm
Reading within Erase
Suspended Sector
Reading within Non-Erase
Suspended Sector
Erase-Suspend Program
DQ7
DQ7#
0
1
Data
DQ7#
DQ6
Toggle
Toggle
No
Toggle
Data
Toggle
DQ5
0
0
0
Data
0
DQ3
N/A
1
N/A
Data
N/A
DQ2 RY/BY#
No
toggle
0
Toggle
0
Toggle
1
Data
1
N/A
0
This Data Sheet may be revised by subsequent versions
19
or modifications due to changes in technical specifications.
© 2004 Eon Silicon Solution, Inc.,
Rev. I, Issue Date: 2011/10/26
www.eonssi.com