M25P64
Write Enable (WREN)
The Write Enable (WREN) instruction (Figure
sets the Write Enable Latch (WEL) bit.
The Write Enable Latch (WEL) bit must be set pri-
or to every Page Program (PP), Sector Erase
(SE), Bulk Erase (BE) and Write Status Register
(WRSR) instruction.
The Write Enable (WREN) instruction is entered
by driving Chip Select (S) Low, sending the in-
struction code, and then driving Chip Select (S)
High.
Figure 9. Write Enable (WREN) Instruction Sequence
S
0
C
Instruction
D
High Impedance
Q
AI02281E
1
2
3
4
5
6
7
Write Disable (WRDI)
The Write Disable (WRDI) instruction (Figure
resets the Write Enable Latch (WEL) bit.
The Write Disable (WRDI) instruction is entered by
driving Chip Select (S) Low, sending the instruc-
tion code, and then driving Chip Select (S) High.
The Write Enable Latch (WEL) bit is reset under
the following conditions:
–
–
–
–
–
–
Power-up
Write Disable (WRDI) instruction completion
Write Status Register (WRSR) instruction
completion
Page Program (PP) instruction completion
Sector Erase (SE) instruction completion
Bulk Erase (BE) instruction completion
Figure 10. Write Disable (WRDI) Instruction Sequence
S
0
C
Instruction
D
High Impedance
Q
AI03750D
1
2
3
4
5
6
7
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