EN29LV641H/L EN29LV640U
Flowchart 6b. In-System Sector Group Unprotect Flowchart
START
PLSCNT = 1
RESET# = VID
Wait 1 µS
Protect all sector
groups: The
indicated portion of
the sector group
protect algorithm
must be performed
for all unprotected
sectors prior to
issuing the first
sector unprotect
address (see
No
Temporary Sector
First Write
Cycle = 60h?
Group Unprotect Mode
Diagram 6a.)
Yes
No
All sectors
protected?
Yes
Set up first sector
group address
Unprotect: Write 60H to sector
address with A6 = 1,
A1 = 1, A0 = 0
Wait 15 ms
Verify Unprotect: Write 40h
to sector address with A6 =
1, A1 = 1, A0 =0
Increment
PLSCNT
Wait 0.4 µS
Read from sector group address
with A6 = 1, A1 = 1, A0 = 0
No
No
PLSCCNT =
1000?
Set up next sector
group address
Data = 00h?
Yes
Yes
No
Last sector
group
Device failed
verified?
Yes
Remove VID from
RESET#
Write reset
command
Sector Group
Unprotect complete
Sector Group Unprotect Algorithm
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
©2005 Eon Silicon Solution, Inc., www.essi.com.tw
29
Rev. B, Issue Date: 2005/06/27
EON [ EON SILICON SOLUTION INC. ]
