Block Unlock Flow
start
RDSCUR(2Bh) command
No
WPSEL=1?
Yes
WREN command
SBULK command
( 39h + 24bit address )
RDSR command
No
WIP=0?
Yes
RDPLOCK command to verify
WPSEL command
MX25L12855E
No
Data = FFh ?
Yes
Block is permanently locked,
cannot be unlocked
RDBLOCK command to verify
( 3Ch + 24bit address )
Yes
Data = FF ?
No
Block unlock successfully
Block unlock fail
Unlock another block?
Yes
Unlock block completed?
P/N: PM1466
REV. 0.05, MAR. 05, 2009
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