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AM29LV065D_06 Datasheet, PDF (18/54 Pages) Advanced Micro Devices – 64 Megabit (8 M x 8-Bit) CMOS 3.0 Volt-only Uniform Sector Flash Memory with VersatileIOTM Control | |||
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Sector Group Protection and
Unprotection
The hardware sector group protection feature disables
both program and erase operations in any sector
group. In this device, a sector group consists of four
adjacent sectors that are protected or unprotected at
the same time (see Table 4). The hardware sector
group unprotection feature re-enables both program
and erase operations in previously protected sector
groups. Sector group protection/unprotection can be
implemented via two methods.
Sector protection and unprotection requires VID on the
RESET# pin only, and can be implemented either
in-system or via programming equipment. Figure 2
shows the algorithms and Figure 23 shows the timing
diagram. This method uses standard microprocessor
bus cycle timing. For sector group unprotect, all unpro-
tected sector groups must first be protected prior to
the first sector group unprotect write cycle.
The device is shipped with all sector groups unpro-
tected. AMD offers the option of programming and pro-
tecting sector groups at its factory prior to shipping the
device through AMDâs ExpressFlash⢠Service. Con-
tact an AMD representative for details.
It is possible to determine whether a sector group is
protected or unprotected. See the Autoselect Mode
section for details.
Table 4. Sector Group Protection/Unprotection
Address Table
Sector Group
A22âA18
SA0âSA3
SA4âSA7
00000
00001
SA8âSA11
SA12âSA15
00010
00011
SA16âSA19
SA20âSA23
00100
00101
SA24âSA27
SA28âSA31
00110
00111
SA32âSA35
SA36âSA39
SA40âSA43
01000
01001
01010
SA44âSA47
SA48âSA51
01011
01100
SA52âSA55
SA56âSA59
01101
01110
SA60âSA63
SA64âSA67
01111
10000
SA68âSA71
SA72âSA75
10001
10010
SA76âSA79
SA80âSA83
SA84âSA87
10011
10100
10101
SA88âSA91
SA92âSA95
10110
10111
SA96âSA99
SA100âSA103
11000
11001
SA104âSA107
SA108âSA111
11010
11011
SA112âSA115
SA116âSA119
SA120âSA123
11100
11101
11110
SA124âSA127
11111
Note: All sector groups are 256 Kbytes in size.
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Am29LV065D
February 16, 2006
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