Deasserting the CS pin will terminate the Manufacturer and Device ID Read operation and put
the SO pin into a high-impedance state. The CS pin can be deasserted at any time and does not
require that a full byte of data be read.
14.1 Manufacturer and Device ID Information
14.1.1
Byte 1 – Manufacturer ID
JEDEC Assigned Code
Hex
Value
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
1FH
0
0
0
1
1
1
1
1
Manufacturer ID
1FH = Atmel
14.1.2
Byte 2 – Device ID (Part 1)
Family Code
Density Code
Hex
Family Code
Density Code
001 = DataFlash
00101 = 8-Mbit
Value
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
25H
0
0
1
0
0
1
0
1
14.1.3
Byte 3 – Device ID (Part 2)
MLC Code
Product Version Code
Hex
MLC Code
000 = 1-bit/Cell Technology
00000 = Initial Version
Value
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
00H
0
0
0
0
0
0
0
0
Product Version
14.1.4
Byte 4 – Extended Device Information String Length
Byte Count
Hex
Value
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
00H
0
0
0
0
0
0
0
0
Byte Count
00H = 0 Bytes of Information
CS
9FH
Opcode
SI
1FH
25H
00H
00H
Data
Data
SO
Manufacturer ID
Byte n
Device ID
Byte 1
Device ID
Byte 2
Extended
Device
Information
String Length
Extended
Device
Information
Byte x
Extended
Device
Information
Byte x + 1
Each transition
represents 8 bits
This information would only be output
if the Extended Device Information String Length
value was something other than 00H.
Note:
Based on JEDEC publication 106 (JEP106), Manufacturer ID data can be comprised of any number of bytes. Some manufacturers may have
Manufacturer ID codes that are two, three or even four bytes long with the first byte(s) in the sequence being 7FH. A system should detect code
7FH as a “Continuation Code” and continue to read Manufacturer ID bytes. The first non-7FH byte would signify the last byte of Manufacturer ID
data. For Atmel (and some other manufacturers), the Manufacturer ID data is comprised of only one byte.
26
AT45DB081D
3596E–DFLASH–02/07
ATMEL [ ATMEL ]
