AM29LV320MH Datasheet, PDF (18/59 Pages) SPANSION – 32 Megabit (2 M x 16-Bit/4 M x 8-Bit) MirrorBit 3.0 Volt-only Uniform Sector Flash Memory with VersatileI/O Control

DATASHEET
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/unprotection requires V_ID on the RE-
SET# pin only, and can be implemented either in-sys-
tem or via programming equipment. Figure 2 shows
the algorithms and Figure 24 shows the timing dia-
gram. 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 AMD’s 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
A20–A15
SA0
000000
SA1
000001
SA2
000010
SA3
000011
SA4–SA7
SA8–SA11
0001xx
0010xx
SA12–SA15
SA16–SA19
0011xx
0100xx
SA20–SA23
SA24–SA27
SA28–SA31
0101xx
0110xx
0111xx
SA32–SA35
SA36–SA39
1000xx
1001xx
SA40–SA43
SA44–SA47
1010xx
1011xx
SA48–SA51
SA52–SA55
1100xx
1101xx
SA56–SA59
SA60
1110xx
111100
SA61
SA62
SA63
111101
111110
111111
16
Am29LV320MH/L
December 14, 2005