S25FL040A Meet Spansion Inc., S25FL040A Datasheet - Page 19

• Manufacturer Part Number: S25FL040A
• Description: Small Sector For Boot And Parameter Storage 4-megabit Cmos 3.0 Volt Flash Memory With 50 Mhz Spi Bus Interface
• Manufacturer: Meet Spansion Inc.

9.4
July 2, 2007 S25FL040A_00_B2
SCK
CS#
SO
SI
Read Identification (Read_ID) [RDID Alternate]
0
The READ_ID instruction provides the S25FL040A manufacturer and device information. This command
should be used as default device identification when multiple versions of SPI Serial Flash devices are used in
a design.
The device information can be read from by writing the 8-bit command (90H) followed by address bits.
Following the READ_ID instruction, the manufacturer’s ID is located at address 00000H and the device ID
(Memory Capacity) is located at address 00001H. Once the device is in READ_ID mode, the manufacturer’s
and device ID output data toggles between address 00000H and 00001H until CE# is driven high.
1
High Impedance
2
Instruction
Device Identification (Memory Capacity)
3
4
Manufacturer Identification
5
6
7
23 22 21
MSB
8
D a t a
9
Figure 9.4 READ_ID Command Timing Diagram
24-Bit Address
10
Table 9.2 READ_ID Data-Out Sequence
S h e e t
3
28
2
S25FL040A
29
1
30
0
31
32
Manufacture Identification
33
Address
00000h
00001h
34
35
36
37
38
Uniform
39
01h
12h
40
7
41
6
Device Identification
42
5
Top Boot
43
4
Data
01h
25h
44
3
2
45
1
46
Bottom Boot
0
47
01h
26h
19