en29lv800bt-90tip Eon Silicon Solution Inc., en29lv800bt-90tip Datasheet - Page 16

• Manufacturer Part Number: en29lv800bt-90tip
• Description: 8 Megabit 1024k X 8-bit / 512k X 16-bit Flash Memory Boot Sector Flash Memory, Cmos 3.0 Volt-only
• Manufacturer: Eon Silicon Solution Inc.

Flowchart 6 shows the toggle bit algorithm, and the section “DQ2: Toggle Bit” explains the algorithm.
See also the “DQ6: Toggle Bit I” subsection. Refer to the Toggle Bit Timings figure for the toggle bit
timing diagram. The DQ2 vs. DQ6 figure shows the differences between DQ2 and DQ6 in graphical
form.
Reading Toggle Bits DQ6/DQ2
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
Suspend
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
Standar
d Mode
Erase
Mode
Embedded Erase Algorithm
Reading within Non-Erase
Erase-Suspend Program
Operation
Reading within Erase
Embedded Program
Suspended Sector
Suspended Sector
Algorithm
Rev. H, Issue Date: 2008/07/07
DQ7#
DQ7#
Data
DQ7
0
1
16
Toggle
Toggle
Toggle
Toggle
DQ6
Data
No
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
DQ5
Data
0
0
0
0
DQ3
Data
N/A
N/A
N/A
1
EN29LV800B
Toggle
Toggle
toggle
DQ2
Data
N/A
No
RY/BY
#
0
0
1
1
0