AM41PDS3224DB100IS AMD [Advanced Micro Devices], AM41PDS3224DB100IS Datasheet - Page 21

• Manufacturer Part Number: AM41PDS3224DB100IS
• Description: 32 Megabit (2 M x 16-Bit) CMOS 1.8 Volt-only, Simultaneous Operation, Page Mode Flash Memory and 4 Mbit (512 K x 8-Bit/256 K x 16-Bit) Static RAM
• Manufacturer: AMD [Advanced Micro Devices]

Note: The term “sector” in the figure applies to both sectors and sector blocks.
20
Sector Protect
Temporary Sector
Unprotect Mode
Algorithm
Device failed
Increment
PLSCNT
PLSCNT
= 25?
No
Yes
Figure 2. In-System Sector/Sector Block Protect and Unprotect Algorithms
No
No
Write 60h to sector
Protect: Write 40h
to sector address
A6 = 0, A1 = 1,
Protect another
Sector Protect:
sector address
RESET# = V
A1 = 1, A0 = 0
A1 = 1, A0 = 0
Sector Protect
Verify Sector
from RESET#
Set up sector
Cycle = 60h?
Remove V
PLSCNT = 1
address with
with A6 = 0,
with A6 = 0,
Data = 01h?
Wait 150 µs
Write reset
Read from
First Write
command
Wait 1 s
complete
address
START
sector?
A0 = 0
Yes
Yes
No
ID
ID
Yes
PLSCNT = 1
P R E L I M I N A R Y
Reset
Am41PDS3224D
The indicated portion
unprotected sectors
Protect all 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 s
All sectors
complete
address
verified?
START
A0 = 0
A0 = 0
Yes
Yes
Yes
Yes
ID
ID
No
No
Temporary Sector
May 13, 2002
Unprotect Mode
next sector
address
Set up