am42dl1614dt70it Meet Spansion Inc., am42dl1614dt70it Datasheet - Page 19

• Manufacturer Part Number: am42dl1614dt70it
• Description: 16 Mbit X8/x16 Flash And 4 Mbit X16 Static Ram Preliminary
• Manufacturer: Meet Spansion Inc.

If the system asserts V
vice disables program and erase functions in the two
“outermost” 8 Kbyte boot sectors independently of
whether those sectors were protected or unprotected
using the method described in “The autoselect mode
provides manufacturer and device identification, and
sector protection verification, through identifier codes
output on DQ7–DQ0. The autoselect codes can be ac-
cessed in-system through the command register.
Refer to the Autoselect Command Sequence section
for more information.Sector/Sector Block Protection
and Unprotection”. The two outermost 8 Kbyte boot
sectors are the two sectors containing the lowest ad-
dresses in a top-boot-configured device, or the two
se ct ors con tain in g th e hig he st a dd resse s in a
top-boot-configured device.
If the system asserts V
vice reverts to whether the two outermost 8 Kbyte boot
sectors were last set to be protected or unprotected.
That is, sector protection or unprotection for these two
sectors depends on whether they were last protected
or unprotected using the method described in “The au-
toselect mode provides manufacturer and device
identification, and sector protection verification,
through identifier codes output on DQ7–DQ0. The au-
toselect codes can be accessed in-system through the
command register. Refer to the Autoselect Command
Sequence section for more information.Sector/Sector
Block Protection and Unprotection”.
Note that the WP#/ACC pin must not be left floating or
unconnected; inconsistent behavior of the device may
result.
Temporary Sector/Sector Block Unprotect
(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 Tables
8 and 9).
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on the WP#/ACC pin, the de-
on the WP#/ACC pin, the de-
P R E L I M I N A R Y
Am42DL16x4D
This feature allows temporary unprotection of previ-
ously protected sectors to change data in-system. The
Sector Unprotect mode is activated by setting the RE-
SET# pin to V
formerly protected sectors can be programmed or
erased by selecting the sector addresses. Once V
removed from the RESET# pin, all the previously pro-
tected sectors are protected again. Figure 1 shows the
algorithm, and Figure 25 shows the timing diagrams,
for this feature.
Notes:
1. All protected sectors unprotected (If WP#/ACC = V
2. All previously protected sectors are protected once
Figure 1. Temporary Sector Unprotect Operation
outermost boot sectors will remain protected).
again.
ID
(8.5 V – 12.5 V). During this mode,
Unprotect Completed
Program Operations
Temporary Sector
Perform Erase or
RESET# = V
RESET# = V
(Note 1)
(Note 2)
START
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January 9, 2002
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