Operating features
M25PE80
Table 2.
Software protection truth table (sectors 0 to 15, 64-Kbyte granularity)
Sector lock register
Protection status
Lock
Write
down bit
lock bit
0
0
0
1
Sector unprotected from program/erase/write operations, protection status reversible
Sector protected from program/erase/write operations, protection status reversible
Sector unprotected from program/erase/write operations,
Sector protection status cannot be changed except by a reset or power-up.
1
1
0
1
Sector protected from program/erase/write operations,
Sector protection status cannot be changed except by a reset or power-up.
Table 3.
Not for new design: TY7 process only, software protection scheme truth
table (sectors 0 and 15)
(1) (2) (3)
Sector lock Subsector lock
register register
Protection status
Lock Write Lock Write
down lock
down
bit
lock
bit
bit
bit
Current subsector unprotected from program/erase/write operations,
Current subsector protection status reversible
0
0
1
1
0
1
1
1
1
0
1
0
1
1
1
0
1
1
Current subsector protected from program/erase/write operations,
Current subsector protection status reversible.
0
Current subsector unprotected from program/erase/write operations, current
subsector protection status cannot be changed except by a reset or power-up.
0
Current subsector protected from program/erase/write operations, Current
subsector protection status cannot be changed except by a reset or power-up.
All subsectors protected from program/erase/write operations, current subsector
protection status reversible
1
All subsectors protected from program/erase/write operations, current subsector
protection status cannot be changed except by a reset or power-up.
Current subsector unprotected from program/erase/write operations, all
subsectors protection status cannot be changed except by a reset or power-up
0
1
Current subsector protected from program/erase/write operations, all subsectors
protection status cannot be changed except by a reset or power-up
1
All subsectors protected with their protection status cannot be changed except by
a reset or power-up.
1. All other bit combinations are not-applicable.
2. For more details, refer to the description of the Write to lock register (WRLR) instruction.
3. See Important note on page 6 for differences between devices produced in T7Y and T9HX processes.
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