W25Q80BV
- 56 -
7.2.36
Read SFDP Register (5Ah)
The W25Q80BV features a 256-Byte Serial Flash Discoverable Parameter (SFDP) register that contains
information about devices operational capability such as available commands, timing and other features.
The SFDP parameters are stored in one or more Parameter Identification (PID) tables. Currently only one
PID table is specified but more may be added in the future. The Read SFDP Register instruction is
compatible with the SFDP standard initially established in 2010 for PC and other applications. Most
Winbond SpiFlash Memories shipped after June 2010 (date code 1023 and beyond) support the SFDP
feature as specified in the applicable datasheet.
The Read SFDP
instruction is initiated by driving the /CS pin low and shifting the instruction code “5Ah”
followed by a 24-bit address (A23-A0)
(1)
into the DI pin. Eight “dummy” clocks are also required before the
SFDP register contents are shifted out on the falling edge of the 40
th
CLK with most significant bit (MSB)
first as shown in figure 34. For SFDP register values and descriptions, please refer to the Winbond
Application Note for SFDP Definition table.
Note: 1. A23-A8 = 0; A7-A0 are used to define the starting byte address for the 256-Byte SFDP Register.
/CS
CLK
DI
(IO
0
)
DO
(IO
1
)
Mode 0
Mode 3
0
1
2
3
4
5
6
7
Instruction (5Ah)
High Impedance
8
9
10
28
29
30
31
24-Bit Address
23
22
21
3
2
1
0
Data Out 1
*
/CS
CLK
DI
(IO
0
)
DO
(IO
1
)
32
33
34
35
36
37
38
39
Dummy Byte
High Impedance
40
41
42
44
45
46
47
48
49
50
51
52
53
54
55
7
6
5
4
3
2
1
0
7
Data Out 2
*
7
6
5
4
3
2
1
0
*
7
6
5
4
3
2
1
0
43
31
0
= MSB
*
Figure 34. Read SFDP Register Instruction Sequence Diagram