SA25F020 Datasheet, PDF (22/37 Pages) List of Unclassifed Manufacturers – 2Mb Serial Flash with 25MHz SPI Bus Interface

The WRSR command requires the
following sequence:
1. The CSb pin is pulled low to select
the device.
CS
SA25F020 Advanced Information
SAIFUN
22
2. The WRSR opcode is then
transmitted on the SI pin, followed
by the data to be programmed.
The instruction sequence is shown in
Figure 13.
SCK
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Instruction
Status Register In
SI
765 43 2 1 0
MSB
SO
High Impedance
Figure 13. Write Status Register (WRSR) Instruction Sequence