W25Q64DW_12 Datasheet, PDF (59/82 Pages) Winbond – 1.8V 64M-BIT SERIAL FLASH MEMORY WITH DUAL/QUAD SPI & QPI

W25Q64DW
10.2.34 Read JEDEC ID (9Fh)
For compatibility reasons, the W25Q64DW provides several instructions to electronically determine the
identity of the device. The Read JEDEC ID instruction is compatible with the JEDEC standard for SPI
compatible serial memories that was adopted in 2003. The instruction is initiated by driving the /CS pin low
and shifting the instruction code “9Fh”. The JEDEC assigned Manufacturer ID byte for Winbond (EFh) and
two Device ID bytes, Memory Type (ID15-ID8) and Capacity (ID7-ID0) are then shifted out on the falling
edge of CLK with most significant bit (MSB) first as shown in Figure 33a & 33b. For memory type and
capacity values refer to Manufacturer and Device Identification table.
/CS
CLK
DI
(IO₀)
DO
(IO₁)
/CS
CLK
Mode 3
Mode 0
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Instruction (9Fh)
* ^{= MSB}
High Impedance
Manufacturer ID (EFh)
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
Mode 3
Mode 0
DI
(IO₀)
DO
(IO₁)
Memory Type ID15-8
Capacity ID7-0
7654321076543210
*
*
Figure 33a. Read JEDEC ID Instruction (SPI Mode)
/CS
CLK
IO₀
Mode 3
Mode 0
012
Instruction
9Fh
3456
IOs switch from
Input to Output
12 8 4 0
IO₁
13 9 5 1
IO₂
14 10 6 2
IO₃
15 11 7 3
EFh
ID15-8 ID7-0
Mode 3
Mode 0
Figure 33b. Read JEDEC ID Instruction (QPI Mode)
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Publication Release Date: September 18, 2012
Revision D