1 sector protection register – Rainbow Electronics AT45DB021D User Manual
Page 12
12
3638K–DFLASH–11/2012
AT45DB021D
The table below details the sector protection status for various scenarios of the WP pin, the Enable Sector
Protection command, and the Disable Sector Protection command.
Figure 7-1.
WP Pin and Protection Status
Table 7-1.
WP Pin and Protection Status
7.1
Sector Protection Register
The nonvolatile Sector Protection Register specifies which sectors are to be protected or unprotected with either
the software or hardware controlled protection methods. The Sector Protection Register contains 8-bytes of data,
of which byte locations zero through seven contain values that specify whether sectors zero through seven will be
protected or unprotected. The Sector Protection Register is user modifiable and must first be erased before it can
be reprogrammed.
illustrates the format of the Sector Protection Register
Table 7-2.
Sector Protection Register.
Table 7-3.
Sector 0 (0a, 0b)
Note:
1. The default value for bytes 0 through 7 when shipped from Adesto is 00H
x = don’t care
Time
Period
WP Pin
Enable Sector Protection
Command
Disable Sector
Protection Command
Sector
Protection Status
Sector
Protection
Register
1
High
Command Not Issued Previously
–
Issue Command
X
Issue Command
–
Disabled
Disabled
Enabled
Read/Write
Read/Write
Read/Write
2
Low
X
X
Enabled
Read Only
3
High
Command Issued During Period 1
or 2
–
Issue Command
Not Issued Yet
Issue Command
–
Enabled
Disabled
Enabled
Read/Write
Read/Write
Read/Write
WP
1
2
3
Sector Number
0 (0a, 0b)
1 to 7
Protected
See
FFH
Unprotected
00H
0a
0b
Bit 3, 2
Data
Value
(Page 0-7)
(Page 8-127)
Bit 7, 6
Bit 5, 4
Bit 1, 0
Sectors 0a, 0b Unprotected
00
00
xx
xx
0xH
Protect Sector 0a
11
00
xx
xx
CxH
Protect Sector 0b (Page 8-127)
00
11
xx
xx
3xH
Protect Sectors 0a (Page 0-7), 0b (Page 8-127)
11
11
xx
xx
FxH