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28
8210C–AVR–09/11
Atmel AVR XMEGA D
Note:
1. See device datasheet for alternate TOSC position.
• Bit 4:2 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always
write these bits to one when this register is written.
• Bit 1:0 – BODPD[1:0]: BOD Operation in Power-down Mode
These fuse bits set the BOD operation mode in all sleep modes except idle mode.
For details on the BOD and BOD operation modes refer to
”Brownout Detection” on page 89
4.13.3
FUSEBYTE4 – Fuse Byte4
• Bit 7:5 – Reserved
These bits are unused and reserved for future use. For compatibility with future devices, always
write these bits to one when this register is written.
• Bit: 4 – RSTDISBL: External Reset Disable
This fuse can be programmed to disable the external reset pin functionality. When this is done
pulling th pin low will not cause an external reset. A reset is required before this bit will be read
correctly after it is changed.
• Bit 3:2 – STARTUPTIME[1:0]: Start-up time
These fuse bits can be used to set at a programmable timeout period from all reset sources are
released until the internal reset is released from the delay counter. A reset is required before
these bits will be read correctly after they are changed.
The delay is timed from the 1kHz output of the ULP oscillator. Refer to
for details.
Table 4-2.
TOSCSEL fuse.
TOSCSEL
Group Configuration
Description
0
ALTERNATE
TOSC1/2 on separate pins
1
XTAL
TOSC1/2 shared with XTAL
Table 4-3.
BOD operation modes in sleep modes.
BODPD[1:0]
Description
00
Reserved
01
BOD enabled in sampled mode
10
BOD enabled continuously
11
BOD disabled
Bit
7
6
5
4
3
2
1
0
+0x04
–
–
–
RSTDISBL
STARTUPTIME[1:0]
WDLOCK
–
FUSEBYTE4
Read/Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Initial Value
1
1
1
1
1
1
1
0