AM29LV642D AMD [Advanced Micro Devices], AM29LV642D Datasheet - Page 24

• Manufacturer Part Number: AM29LV642D
• Manufacturer: AMD [Advanced Micro Devices]

22
Sector Group
Temporary Sector
Group Unprotect
Algorithm
Device failed
Protect
Increment
PLSCNT
PLSCNT
Mode
= 25?
No
Yes
No
No
Sector Group Protect:
address twith A6 = 0,
sector group address
Verify Sector Group
group address with
Figure 2. In-System Sector Group Protect/Unprotect Algorithms
Write 60h to sector
Protect: Write 40h
Protect complete
A6 = 0, A1 = 1,
to sector group
RESET# = V
group address
A1 = 1, A0 = 0
A1 = 1, A0 = 0
Sector Group
from RESET#
Set up sector
sector group?
PLSCNT = 1
Cycle = 60h?
Remove V
with A6 = 0,
Wait 150 µs
Data = 01h?
Write reset
Read from
First Write
command
Wait 1 μs
START
another
Protect
A0 = 0
Yes
Yes
No
ID
ID
Yes
PLSCNT = 1
D A T A
Reset
Am29LV642D
must be performed for all
group protect algorithm
groups: The indicated
groups prior to issuing
the first sector group
portion of the sector
S H E E T
unprotected sector
Protect all sector
unprotect address
Sector Group
Unprotect
Algorithm
Device failed
Increment
PLSCNT
PLSCNT
= 1000?
No
Yes
No
No
address with A6 = 1,
Verify Sector Group
40h to sector group
Unprotect complete
Write 60h to sector
group address with
Set up first sector
Unprotect: Write
A6 = 1, A1 = 1,
A6 = 1, A1 = 1,
RESET# = V
group address
Sector Group
A1 = 1, A0 = 0
from RESET#
Sector Group
address with
Cycle = 60h?
sector group
Remove V
PLSCNT = 1
Data = 00h?
Write reset
Wait 15 ms
Read from
Last sector
First Write
protected?
Unprotect:
command
Wait 1 μs
All sector
verified?
START
groups
A0 = 0
A0 = 0
group
Yes
Yes
Yes
Yes
ID
ID
No
25022A2 May 5, 2006
No
next sector group
Temporary Sector
Group Unprotect
address
Set up
Mode