The instruction set of the FM25Q32 consists of fifteen 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 DI input provides the instruction code.
Data on the DI 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 29. All read instructions can be completed after any clocked bit.
However, all instructions that Write, Program or Erase must complete on a byte (/CS driven high
after a full 8-bit 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 Register will
be ignored until the program or erase cycle has completed.
11.2.1 Manufacturer and Device Identification