Atmel AT90PWM2 Manual page 281

25.3.1 Latching of Fuses
AT90PWM2/3/2B/3B
282
Table 25-5. Fuse High Byte
High Fuse Byte
(1)
RSTDISBL
DWEN
(2)
SPIEN
(3)
WDTON
EESAVE
(4)
BODLEVEL2
(4)
BODLEVEL1
(4)
BODLEVEL0
Notes: 1. See "Alternate Functions of Port C" on page 72
2. The SPIEN Fuse is not accessible in serial programming mode.
3. See "Watchdog Timer Configuration" on page 55
4. See Table 9-2 on page 49
Table 25-6. Fuse Low Byte
Low Fuse Byte
(4)
CKDIV8
(3)
CKOUT
SUT1
SUT0
CKSEL3
CKSEL2
CKSEL1
CKSEL0
Note: 1. The default value of SUT1..0 results in maximum start-up time for the default clock source.
See Table 7 on page 38
2. The default setting of CKSEL3..0 results in internal RC Oscillator @ 8 MHz. See
page 38 for details.
3. The CKOUT Fuse allows the system clock to be output on PORTB0. See
Buffer" on page 38
4. See "System Clock Prescaler" on page 38
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.
The fuse values are latched when the device enters programming mode and changes of the
fuse values will have no effect until the part leaves Programming mode. This does not apply to
the EESAVE Fuse which will take effect once it is programmed. The fuses are also latched on
Power-up in Normal mode.
Bit No Description
7 External Reset Disable
6 debugWIRE Enable
Enable Serial Program and
5
Data Downloading
4 Watchdog Timer Always On
EEPROM memory is
3 preserved through the Chip
Erase
Brown-out Detector trigger
2
level
Brown-out Detector trigger
1
level
Brown-out Detector trigger
0
level
for BODLEVEL Fuse decoding.
Bit No Description
7 Divide clock by 8
6 Clock output
5 Select start-up time
4 Select start-up time
3 Select Clock source
2 Select Clock source
1 Select Clock source
0 Select Clock source
for details.
for details.
for details.
Default Value
1 (unprogrammed)
1 (unprogrammed)
0 (programmed, SPI
programming enabled)
1 (unprogrammed)
1 (unprogrammed), EEPROM
not reserved
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
for description of RSTDISBL Fuse.
for details.
Default Value
0 (programmed)
1 (unprogrammed)
1 (unprogrammed)
0 (programmed)
0 (programmed)
0 (programmed)
1 (unprogrammed)
0 (programmed)
(1)
(1)
(2)
(2)
(2)
(2)
Table 7 on
"Clock Output
4317I–AVR–01/08