SA25F020 Datasheet, PDF (17/37 Pages) List of Unclassifed Manufacturers – 2Mb Serial Flash with 25MHz SPI Bus Interface

Functional Description
Instructions
Figure 9 presents a schematic diagram of
the SA25F020's SPI serial interface.
MASTER:
MICROCONTROLLER
DATA OUT
DATA IN
SERIAL CLOCK
SSO
SS1
SS2
SS3
SLAVE
SA25F020
SI
SO
SCK
CSb
SI
SO
SCK
CSb
SI
SO
SCK
CSb
SI
SO
SCK
CSb
Figure 9. SPI Serial Interface
SA25F020 Advanced Information
SAIFUN
17
The SA25F020's SPI consists of an 8-bit
instruction register that decodes a specific
instruction to be executed. Thirteen
different instructions (called opcodes) are
incorporated in the device for various
operations. Table 6 lists the instruction set
and the format for proper operation. All
opcodes, array addresses and data are
transferred in an MSB-first-LSB-last
fashion. Detailed information about each of
these opcodes is provided for the individual
instruction descriptions in the sections that
follow.
Table 6. Instruction Set
Instruction
Name
Instruction
Format
Operation
WREN
WRDI
RDSR
WRSR
READ
FAST_READ
Page
Program
PE
SE
BE
SP
RES
READ_ID
0000 0110
Set Write Enable
Latch
0000 0100
Reset Write Enable
Latch
0000 0101
Read Status
Register
0000 0001
Write Status
Register
0000 0011
Read Data from
Memory Array
0000 1011
Read Data from
Memory Array
0000 0010
Write Data to
Memory Array
1000 0001
Page Erase
1101 1000
Sector Erase
1100 0111
Bulk Erase
1011 1001
Software Protect
1010 1011
Release from
Software Protect
Mode
1010 1011
+3 dummy bytes
Release from
Software Protect +
Read ID
1010 1011
+3 dummy bytes
Read ID