ATMEGA64RFR2_14 Datasheet, PDF (516/611 Pages) ATMEL Corporation – Microcontroller with Low Power

31.8.12 Reading the Fuse and Lock Bits
The algorithm for reading the Fuse and Lock bits is as follows (refer to "Programming
the Flash" on page 511 for details on Command and Data loading):
1. A: Lo_a_d Command “0000 0100”.
2. Set OE to “0”, and BS2, BS1 to “00”. The status of the Fuse Low bits can now be
read_a_t DATA (“0” means programmed).
3. Set OE to “0”, and BS2, BS1 to “11”. The status of the Fuse High bits can now be
read_a_t DATA (“0” means programmed).
4. Set OE to “0”, and BS2, BS1 to “10”. The status of the Extended Fuse bits can now
be re_a_d at DATA (“0” means programmed).
5. Set OE to “0”, and BS2, BS1 to “01”. The status of the Lock bits can now be read at
DAT_A_(“0” means programmed).
6. Set OE to “1”.
Figure 31-9. Mapping between BS1, BS2 and the Fuse and Lock Bits during Read
Fuse Low Byte
0
Extended Fuse Byte
1
BS2
Lock Bits
0
Fuse High Byte
1
BS2
0
DATA
1
BS1
31.8.13 Reading the Signature Bytes
The algorithm for reading the Signature bytes is as follows (refer to "Programming the
Flash" on page 511 for details on Command and Data loading):
1. A: Load Command “0000 1000”.
2. B: Lo_a_d Address Low Byte (0x00 - 0x02).
3. Set O__E to “0” and BS to “0”. The selected Signature byte can now be read at DATA.
4. Set OE to “1”.
31.8.14 Reading the Calibration Byte
The algorithm for reading the Calibration byte is as follows (refer to "Programming the
Flash" on page 511 for details on Command and Data loading):
1. A: Load Command “0000 1000”.
2. B: Lo_a_d Address Low Byte, 0x00.
3. Set O__E to “0” and BS1 to “1”. The Calibration byte can now be read at DATA.
4. Set OE to “1”.
516 _{ATmega256/128/64RFR2}
8393C-MCU Wireless-09/14