Datasheet

263
ATmega48PA/88PA/168PA [DATASHEET]
9223F–AVR–04/14
Figure 28-6. Mapping Between BS1, BS2 and the Fuse and Lock Bits During Read
28.7.13 Reading the Signature Bytes
The algorithm for reading the signature bytes is as follows (refer to Section 28.7.4 “Programming the Flash” on page 258 for
details on command and address loading):
1. A: Load command “0000 1000”.
2. B: Load address low byte (0x00 - 0x02).
3. Set OE
to “0”, and BS1 to “0”. The selected signature byte can now be read at DATA.
4. Set OE to “1”.
28.7.14 Reading the Calibration Byte
The algorithm for reading the calibration byte is as follows (refer to Section 28.7.4 “Programming the Flash” on page 258 for
details on command and address loading):
1. A: Load command “0000 1000”.
2. B: Load address low byte, 0x00.
3. Set OE
to “0”, and BS1 to “1”. The calibration byte can now be read at DATA.
4. Set OE
to “1”.
28.7.15 Parallel Programming Characteristics
For characteristics of the parallel programming, see Section 29.9 “Parallel Programming Characteristics” on page 277.
Extended Fuse Byte
0
1
Fuse Low Byte
BS2
Fuse High Byte
0
1
Lock Bits
BS2
BS1
DATA
0
1