The device has three Fuse bytes. The following tables describe briefly the functionality of all the fuses and how they are mapped into the Fuse bytes. Note that the fuses are read as logical zero, '0', if they are programmed.
Low Fuse Byte | Bit No. | Description | Default Value |
---|---|---|---|
CKDIV8(4) | 7 | Divide clock by 8 | 0 (programmed) |
CKOUT(3) | 6 | Clock output | 1 (unprogrammed) |
SUT1 | 5 | Select start-up time | 1 (unprogrammed)(1) |
SUT0 | 4 | Select start-up time | 0 (programmed)(1) |
CKSEL3 | 3 | Select Clock source | 0 (programmed)(2) |
CKSEL2 | 2 | Select Clock source | 0 (programmed)(2) |
CKSEL1 | 1 | Select Clock source | 1 (unprogrammed)(2) |
CKSEL0 | 0 | Select Clock source | 0 (programmed)(2) |
The status of the Fuse bits is not affected by Chip Erase. Note that the Fuse bits are locked if Lock bit1 (LB1) is programmed. Program the Fuse bits before programming the Lock bits.