M28W640CT, M28W640CB

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Table 9. Protection Status

Note: 1. The lock status is defined by the write protect pin and by DQ1 (‘1’ for a locked-down block) and DQ0 (‘1’ for a locked block) as read

2. All blocks are locked at power-up, so the default configuration is 001 or 101 according to WP status.

Current

(WP, DQ1, DQ0)

(WP, DQ1, DQ0)

Current State

Program/Erase

Allowed

After

Block Lock

Command

After

Block Unlock

Command

After Block

Lock-Down

Command

After

WP transition

1,0,0

yes

1,0,1

1,0,0

1,1,1

0,0,0

no

1,0,1

1,0,0

1,1,1

0,0,1

1,1,0

yes

1,1,1

1,1,0

1,1,1

0,1,1

1,1,1

no

1,1,1

1,1,0

1,1,1

0,1,1

0,0,0

yes

0,0,1

0,0,0

0,1,1

1,0,0

no

0,0,1

0,0,0

0,1,1

1,0,1

0,1,1

no

0,1,1

0,1,1

0,1,1