M25P128 Numonyx, B.V., M25P128 Datasheet - Page 25

• Manufacturer Part Number: M25P128
• Description: 128 Mbit (Multilevel), low-voltage, Serial Flash memory with 50-MHz SPI bus interface
• Manufacturer: Numonyx, B.V.

M25P128
Latch (WEL) bit has previously been set by a Write Enable (WREN) instruction, regardless
of the whether Write Protect (W/V
When the Status Register Write Disable (SRWD) bit of the Status Register is set to 1, two
cases need to be considered, depending on the state of Write Protect (W/V
●
●
Regardless of the order of the two events, the Hardware Protected Mode (HPM) can be
entered:
●
●
The only way to exit the Hardware Protected Mode (HPM) once entered is to pull Write
Protect (W/V
If Write Protect (W/V
never be activated, and only the Software Protected Mode (SPM), using the Block Protect
(BP2, BP1, BP0) bits of the Status Register, can be used.
Figure 12. Write Status Register (WRSR) instruction sequence
If Write Protect (W/V
provided that the Write Enable Latch (WEL) bit has previously been set by a Write
Enable (WREN) instruction.
If Write Protect (W/V
even if the Write Enable Latch (WEL) bit has previously been set by a Write Enable
(WREN) instruction. (Attempts to write to the Status Register are rejected, and are not
accepted for execution). As a consequence, all the data bytes in the memory area that
are software protected (SPM) by the Block Protect (BP2, BP1, BP0) bits of the Status
Register, are also hardware protected against data modification.
by setting the Status Register Write Disable (SRWD) bit after driving Write Protect
(W/V
or by driving Write Protect (W/V
(SRWD) bit.
PP
S
C
D
Q
) Low
PP
) High.
PP
) is permanently tied High, the Hardware Protected Mode (HPM) can
0
PP
PP
1
High Impedance
) is driven High, it is possible to write to the Status Register
) is driven Low, it is not possible to write to the Status Register
2
Instruction
3
PP
4
) is driven High or Low.
PP
5
) Low after setting the Status Register Write Disable
6
7
MSB
7
8
6
9 10 11 12 13 14 15
5
Register In
4
Status
3
2
1
0
AI02282D
PP
):
Instructions
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