W29GL032C_13 Datasheet, PDF (22/68 Pages) Winbond – 32M-BIT 3.0-VOLT PARALLEL FLASH MEMORY WITH PAGE MODE

W29GL032C
7.3.1 Lock Register
User can choose Secured Silicon Sector Protection Bit for security sector protection method via setting
the Lock Register bit, DQ0. Lock Register is a 16-bit one time programmable register. Once
programmed DQ0, will be locked in that mode permanently.
Once the Instruction Set Entry instruction sequence for the Lock Register Bits is issued, all sectors
read and write functions are disabled until Lock Register Exit sequence has been executed.
The memory sectors and extended memory sector protection is configured using the Lock Register.
Table 7-10
DQ[15:1]
Don’t Care
Lock Register Bits
DQ0
Secured Silicon Sector Protection Bit
Start
Write Data AAh, Address 555h
Write Data 55h, Address2AAh
Lock Register instruction set entry
Write Data 40h, Address 555h
Write Data A0h, Address don’t care
Write Program Data, Address don’t care
Lock Register data program
Data # Polling Algorithm
YES
Done
NO
NO
DQ5=1
YES
Fail
Pass
Exit lock Register instruction
Reset instruction
Figure 7-2 Lock Register Program Algorithm
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