W25X40BL Datasheet, PDF (13/55 Pages) Winbond – 2.5V 4M-BIT SERIAL FLASH MEMORY WITH 4KB SECTORS AND DUAL I/O SPI

W25X40BL
7.2 INSTRUCTIONS
The instruction set of the W25X40BL consists of nineteen basic instructions that are fully controlled
through the SPI bus (see Instruction Set table). Instructions are initiated with the falling edge of Chip
Select (/CS). The first byte of data clocked into the DIO input provides the instruction code. Data on the
DIO input is sampled on the rising edge of clock with most significant bit (MSB) first.
Instructions vary in length from a single byte to several bytes and may be followed by address bytes,
data bytes, dummy bytes (don’t care), and in some cases, a combination. Instructions are completed
with the rising edge of edge /CS. Clock relative timing diagrams for each instruction are included in
figures 4 through 25. All read instructions can be completed after any clocked bit. However, all
instructions that Write, Program or Erase must complete on a byte boundary (CS driven high after a full
8-bits have been clocked) otherwise the instruction will be terminated. This feature further protects the
device from inadvertent writes. Additionally, while the memory is being programmed or erased, or when
the Status Register is being written, all instructions except for Read Status Register will be ignored until
the program or erase cycle has completed.
7.2.1 Manufacturer and Device Identification
MANUFACTURER ID
(M7-M0)
Winbond Serial Flash
EFh
Device ID
Instruction
W25X40BL
(ID7-ID0)
ABh, 90h, 92h
12h
(ID15-ID0)
9Fh
3013h
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Publication Release Date: April 21, 2011
Preliminary - Revision B