AT45DB321C datasheet(9/37 Pages) ATMEL

9 / 37 page

AT45DB321C [Preliminary]

3387B–DFLSH–9/04

Note:

1. Default value for devices shipped from Atmel.

2. When protecting or unprotecting sector 0b (pages 8-511), we recommend protecting

or unprotecting the entire sector 0b simultaneously.

ERASING THE SECTOR PROTECTION REGISTER: To erase the Sector Protection

4-byte erase command sequence must be clocked in via the SI (serial input) pin. After

the last bit of the command sequence has been clocked in, the CS pin must be deas-

serted to initiate the internally self-timed erase cycle (t

PE). The Ready/Busy status will

indicate that the device is busy during the erase cycle. The erased state of each bit (of a

byte) in the Sector Protection Register indicates that the corresponding sector is flagged

for protection. The RESET pin is disabled during this erase cycle to prevent incomplete

erasure of the Sector Protection Register.

PROGRAMMING THE SECTOR PROTECTION REGISTER: To program the Sector

Protection Register, the CS pin must first be asserted. Once the CS pin has been

asserted, the 4-byte command sequence must be clocked in via the SI (serial input) pin.

After the last bit of the command sequence has been clocked in, the data for the con-

tents of the Sector Protection Register must be clocked in. The first byte corresponds to

sector 0 (0a, 0b), the second byte corresponds to Sector 1 and the last byte (byte 16)

corresponds to Sector 15. After the last bit of data has been clocked in, the CS pin must

be deasserted to initiate the internally self-timed program cycle (t

P). The Ready/Busy

status will indicate that the device is busy during the program cycle. The RESET pin is

disabled during this program cycle to prevent incomplete programming of the sector pro-

tection register.

READING THE SECTOR PROTECTION REGISTER: To read the Sector Protection

4-byte command sequence 32H, 00H, 00H, 00H and 32 don’t care clock cycles must be

clocked in via the SI (serial input) pin. The 32 don’t care clock cycles are required to ini-

Sector 0 (0a, 0b):

–

Data

Value

(Page 8-255)

(Page 256-511)

Bit 6, 7

Bit 4, 5

Bit 2, 3

Bit 0, 1

Sectors 0a, 0b

Unprotected

00H

Protect Sector 0a

C0H

Protect Sector 0b

(Page 8-255)

30H

Protect Sector 0b

(Page 256-511)

0CH

Protect Sectors 0a,

0b (Page 8-255), 0b

(Page 256-511)(1)

FCH

Protect Sectors 0a,

0b (Page 8-255)

F0H

Command

Byte 1

Byte 2

Byte 3

Byte 4

Erase Sector Protection Register

3DH

2AH

7FH

CFH

Command

Byte 1

Byte 2

Byte 3

Byte 4

Program Sector Protection Register

3DH

2AH

7FH

FCH

AT45DB321C датащи(PDF) 9 Page - ATMEL Corporation

AT45DB321C датащи(HTML) 9 Page - ATMEL Corporation

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

датащи скачать

ссылки URL