Am29DL320G 17
Sector/Sector Block Protection and
Unprotection
(Note: For the following discussion, the term “sector”
applies to both sectors and sector blocks. A sector
bl oc k cons ists of two or more adjacent sectors that are
protected or unprotected at the same time (see Tables
2 and 4).
The hardware sector prote ction feature disables both
program and er ase ope rations in an y sec tor. 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.
T able 7. T op Boot Sector/Sector Bloc k Addresses
for Protection/Unprotection
Table 8. Bottom Boot Sector/Sector Block
Addresses for Protection/Unprotection
The primar y method requires V
ID
on the RESET# pin
only, an d can be implemented either in-system or via
programming equipment. Figure 2 shows the algo-
rithms and Figure 26 shows the ti ming diagram. This
method uses standard micr oprocessor bus cycle tim-
ing. For sector unprotect, all unprotected sectors must
first be protected prior to the first sector unprotect
write cycle.
The sector unprotec t algorithm un protects all sectors
in parallel. All previously protected sectors must be in-
dividually re-pro tected. To change data in p rotected
sectors efficiently, the temporary sector unprotect
function is available. See “Tempo rar y Sector Unpro-
tect”.
Sector A20–A12
Sector/
Sector Block Size
SA0
000000XXX 64 Kbytes
SA1-SA3
000001XXX,
000010XXX
000011XXX
192 (3x64) Kbytes
SA4-SA7
0001XXXXX 256 (4x64) Kbytes
SA8-SA11
0010XXXXX 256 (4x64) Kbytes
SA12-SA15
0011XXXXX 256 (4x64) Kbytes
SA16-SA19
0100XXXXX 256 (4x64) Kbytes
SA20-SA23
0101XXXXX 256 (4x64) Kbytes
SA24-SA27
0110XXXXX 256 (4x64) Kbytes
SA28-SA31
0111XXXXX 256 (4x64) Kbytes
SA32-SA35
1000XXXXX 256 (4x64) Kbytes
SA36-SA39
1001XXXXX 256 (4x64) Kbytes
SA40-SA43
1010XXXXX 256 (4x64) Kbytes
SA44-SA47
1011XXXXX 256 (4x64) Kbytes
SA48-SA51
1100XXXXX 256 (4x64) Kbytes
SA52-SA55
1101XXXXX 256 (4x64) Kbytes
SA56-SA59
1110XXXXX 256 (4x64) Kbytes
SA60-SA62
111100XXX,
111101XXX,
111110XXX
192 (3x64) Kbytes
SA63
111111000 8 Kbytes
SA64
111111001 8 Kbytes
SA65
111111010 8 Kbytes
SA66
111111011 8 Kbytes
SA67
111111100 8 Kbytes
SA68
111111101 8 Kbytes
SA69
111111110 8 Kbytes
SA70
111111111 8 Kbytes
Sector A20–A12
Sector/Sector Block
Size
SA70
111111XXX 64 Kbytes
SA69-SA67
111110XXX,
111101XXX,
111100XXX
192 (3x64) Kbytes
SA66-SA63
1110XXXXX 256 (4x64) Kbytes
SA62-SA59
1101XXXXX 256 (4x64) Kbytes
SA58-SA55
1100XXXXX 256 (4x64) Kbytes
SA54-SA51
1011XXXXX 256 (4x64) Kbytes
SA50-SA47
1010XXXXX 256 (4x64) Kbytes
SA46-SA43
1001XXXXX 256 (4x64) Kbytes
SA42-SA39
1000XXXXX 256 (4x64) Kbytes
SA38-SA35
0111XXXXX 256 (4x64) Kbytes
SA34-SA31
0110XXXXX 256 (4x64) Kbytes
SA30-SA27
0101XXXXX 256 (4x64) Kbytes
SA26-SA23
0100XXXXX 256 (4x64) Kbytes
SA22–SA19
0011XXXXX 256 (4x64) Kbytes
SA18-SA15
0010XXXXX 256 (4x64) Kbytes
SA14-SA11
0001XXXXX 256 (4x64) Kbytes
SA10-SA8
000011XXX,
000010XXX,
000001XXX
192 (3x64) Kbytes
SA7
000000111 8 Kbytes
SA6
000000110 8 Kbytes
SA5
000000101 8 Kbytes
SA4
000000100 8 Kbytes
SA3
000000011 8 Kbytes
SA2
000000010 8 Kbytes
SA1
000000001 8 Kbytes
SA0
000000000 8 Kbytes
