AT45DB321D_08 Datasheet, PDF (14/54 Pages) ATMEL Corporation – 32-megabit 2.7-volt DataFlash

9.1 Sector Protection Register
The nonvolatile Sector Protection Register specifies which sectors are to be protected or unpro-
tected with either the software or hardware controlled protection methods. The Sector Protection
Register contains 64 bytes of data, of which byte locations 0 through 63 contain values that
specify whether sectors 0 through 63 will be protected or unprotected. The Sector Protection
Register is user modifiable and must first be erased before it can be reprogrammed. Table 9-3
illustrates the format of the Sector Protection Register.:
Table 9-2. Sector Protection Register
Sector Number
Protected
Unprotected
0 (0a, 0b)
See Table 9-3
1 to 63
FFH
00H
Table 9-3. Sector 0 (0a, 0b)
0a
0b
(Pages 0-7) (Pages 8-127)
Bit 7, 6
Bit 5, 4
Bit 3, 2 Bit 1, 0
Sectors 0a, 0b Unprotected
00
00
xx
xx
Protect Sector 0a (Pages 0-7)
11
00
xx
xx
Protect Sector 0b (Pages 8-127)
00
11
xx
xx
Protect Sectors 0a (Pages 0-7), 0b
(Pages 8-127)⁽¹⁾
11
11
xx
xx
Note: 1. The default value for bytes 0 through 63 when shipped from Atmel is 00H.
x = don’t care.
Data
Value
0xH
CxH
3xH
FxH
14 AT45DB321D
3597J–DFLASH–4/08