AM29DL640H AMD, AM29DL640H Datasheet - Page 19

• Manufacturer Part Number: AM29DL640H
• Description: 64 Megabit CMOS 3.0 Volt-only / Simultaneous Read/Write Flash Memory
• Manufacturer: AMD

February 9, 2005
Sector Protect
Temporary Sector
Unprotect Mode
Algorithm
Device failed
Increment
PLSCNT
PLSCNT
= 25?
No
Yes
No
No
Write 60h to sector
Protect: Write 40h
to sector address
A6 = 0, A1 = 1,
Sector Protect:
sector address
Protect another
RESET# = V
A1 = 1, A0 = 0
A1 = 1, A0 = 0
Sector Protect
from RESET#
Set up sector
Verify Sector
Cycle = 60h?
PLSCNT = 1
address with
Remove V
with A6 = 0,
with A6 = 0,
Wait 150 µs
Data = 01h?
Write reset
Read from
First Write
command
Wait 1 µs
complete
address
START
Figure 2. In-System Sector Protect/Unprotect Algorithms
sector?
A0 = 0
Yes
No
Yes
ID
ID
Yes
PLSCNT = 1
Reset
Am29DL640H
The indicated portion
Protect all sectors:
unprotected sectors
of the sector protect
prior to issuing the
unprotect address
algorithm must be
performed for all
Sector Unprotect
first sector
Algorithm
Device failed
Increment
PLSCNT
PLSCNT
= 1000?
Yes
No
No
No
Write 60h to sector
Set up first sector
Sector Unprotect:
Unprotect: Write
Sector Unprotect
A6 = 1, A1 = 1,
A6 = 1, A1 = 1,
sector address
RESET# = V
A1 = 1, A0 = 0
from RESET#
Verify Sector
40h to sector
address with
PLSCNT = 1
Cycle = 60h?
Remove V
address with
with A6 = 1,
Data = 00h?
Wait 15 ms
Write reset
Read from
First Write
Last sector
protected?
command
Wait 1 µs
All sectors
complete
verified?
address
START
A0 = 0
A0 = 0
Yes
Yes
Yes
Yes
ID
ID
No
No
Temporary Sector
Unprotect Mode
next sector
address
Set up
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