P R E L I M I N A R Y
Sector/Sector Block Protection and
Unprotection
Sector/
Sector Block Size
Sector
A21–A12
SA63–SA66
SA67–SA70
SA71–SA74
SA75–SA78
SA79–SA82
SA83–SA86
SA87–SA90
SA91–SA94
SA95–SA98
SA99–SA102
SA103–SA106
SA107–SA110
SA111–SA114
SA115–SA118
SA119–SA122
SA123–SA126
SA127–SA130
01110XXXXX
01111XXXXX
10000XXXXX
10001XXXXX
10010XXXXX
10011XXXXX
10100XXXXX
10101XXXXX
10110XXXXX
10111XXXXX
11000XXXXX
11001XXXXX
11010XXXXX
11011XXXXX
11100XXXXX
11101XXXXX
11110XXXXX
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
(Note: For the following discussion, the term “sector”
applies to both sectors and sector blocks. A sector
block consists of two or more adjacent sectors that are
protected or unprotected at the same time (see Table
6).
The hardware sector protection feature disables both
program and erase operations in any sector. The hard-
ware sector unprotection feature re-enables both pro-
gram and erase operations in previously protected
sectors. Sector protection/unprotection can be imple-
mented via two methods.
Table 6. Am29DL640G Boot Sector/Sector Block
Addresses for Protection/Unprotection
Sector/
Sector
SA0
SA1
SA2
SA3
SA4
SA5
SA6
SA7
A21–A12
Sector Block Size
0000000000
0000000001
0000000010
0000000011
0000000100
0000000101
0000000110
0000000111
8 Kbytes
8 Kbytes
1111100XXX,
1111101XXX,
1111110XXX
8 Kbytes
SA131–SA133
192 (3x64) Kbytes
8 Kbytes
8 Kbytes
SA134
SA135
SA136
SA137
SA138
SA139
SA140
SA141
1111111000
1111111001
1111111010
1111111011
1111111100
1111111101
1111111101
1111111111
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
8 Kbytes
0000001XXX,
0000010XXX,
0000011XXX,
SA8–SA10
192 (3x64) Kbytes
SA11–SA14
SA15–SA18
SA19–SA22
SA23–SA26
SA27-SA30
SA31-SA34
SA35-SA38
SA39-SA42
SA43-SA46
SA47-SA50
SA51-SA54
SA55–SA58
SA59–SA62
00001XXXXX
00010XXXXX
00011XXXXX
00100XXXXX
00101XXXXX
00110XXXXX
00111XXXXX
01000XXXXX
01001XXXXX
01010XXXXX
01011XXXXX
01100XXXXX
01101XXXXX
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
256 (4x64) Kbytes
The primary method requires VID on the RESET# pin
only, and can be implemented either in-system or via
programming equipment. Figure 2 shows the algo-
rithms and Figure 26 shows the timing diagram. This
method uses standard microprocessor bus cycle tim-
ing. For sector unprotect, all unprotected sectors must
first be protected prior to the first sector unprotect write
cycle. Note that the sector unprotect algorithm unpro-
tects all sectors in parallel. All previously protected
sectors must be individually re-protected. To change
data in protected sectors efficiently, the temporary
sector unprotect function is available. See “Temporary
Sector Unprotect”.
18
Am42DL6404G
March 20, 2002
AMD [ AMD ]
