M49000000G datasheet(20/64 Pages) AMD

20 / 64 page

June 25, 2002

Am49DL320BG

P R E L I M I NARY

Table 8.

Bottom Boot Sector/Sector Block

Addresses for Protection/Unprotection

The hardware sector protection feature disables both

program and erase operations in any sector. The hard-

ware sector unprotection feature re-enables both

program and erase operations in previously protected

sectors. Note that the sector unprotect algorithm un-

protects all sectors in parallel. All previously protected

sectors must be individually re-protected. To change

data in protected sectors efficiently, the temporary

sector un protect function is available. See “Temporary

Sector/Sector Block Unprotect”.

Sector protection and unprotection can be imple-

mented as follows.

Sector protection and unprotection requires V

ID on the

RESET# pin only, and can be implemented either

in-system or via programming equipment. Figure 2

shows the algorithms and Figure 26 shows the timing

diagram. This method uses standard microprocessor

bus cycle timing. For sector unprotect, all unprotected

sectors must first be protected prior to the first sector

unprotect write cycle.

The device is shipped with all sectors unprotected.

It is possible to determine whether a sector is pro-

tected or unprotected. See the Autoselect Mode

section for details.

Write Protect (WP#)

The Write Protect function provides a hardware

method of protecting certain boot sectors without

using V

ID. This function is one of two provided by the

WP#/ACC pin.

If the system asserts V

IL on the WP#/ACC pin, the de-

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 “Autoselect Mode”. The

two outermost 8 Kbyte boot sectors are the two sec-

tors c ontaining t he low e s t addres s e s in a

top-boot-configured device, or the two sectors contain-

ing the highest addresses in a top-boot-configured

device.

If the system asserts V

IH on the WP#/ACC pin, the de-

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 “Autose-

lect Mode”.

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 Table

7).

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

ID (11.5 V – 12.5 V). During this mode,

formerly protected sectors can be programmed or

erased by selecting the sector addresses. Once V

ID is

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.

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

M49000000G Datasheet(PDF) 20 Page - Advanced Micro Devices

M49000000G Datasheet(HTML) 20 Page - Advanced Micro Devices

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64

Datasheet Download

Link URL