The algorithm for reading the Fuse and
Lock bits is as follows (Please refer to Programming the Flash for details on Command loading):
- 1.Step A: Load Command “0000
0100”.
- 2.Set OE to
“0”, BS2 to “0”, and BS1 to “0”. The status of the Fuse Low bits can now be read at
DATA (“0” means programmed).
- 3.Set OE to
“0”, BS2 to “1”, and BS1 to “1”. The status of the Fuse High bits can now be read at
DATA (“0” means programmed).
- 4.Set OE to
“0”, BS2 to “0”, and BS1 to “1”. The status of the Lock Bits can now be read at DATA
(“0” means programmed).
- 5.Set OE to
“1”.
Figure 1. Mapping Between BS1, BS2 and the
Fuse and Lock Bits During Read