ATA8742 ATMEL Corporation, ATA8742 Datasheet - Page 181

• Manufacturer Part Number: ATA8742
• Manufacturer: ATMEL Corporation

28.2
9151A–INDCO–07/09
Fuse Bytes
The ATtiny24/44/84 has three Fuse bytes.
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..
Table 28-3.
Table 28-4.
Notes:
SELFPRGEN
RSTDISBL
DWEN
SPIEN
WDTON
EESAVE
BODLEVEL2
BODLEVEL1
BODLEVEL0
Fuse High Byte
Fuse High Byte
(2)
(3)
1. See
2. DWEN must be unprogrammed when Lock Bit security is required. See
3. The SPIEN Fuse is not accessible in SPI Programming mode.
4. See
5. See
(4)
(1)
Fuses. When programming the RSTDISBL Fuse, High-voltage Serial programming has to be
used to change fuses to perform further programming
Memory Lock Bits” on page
details.
(5)
(5)
(5)
Fuse Extended Byte
Fuse High Byte
“Alternate Functions of Port B” on page 84
“WDT Configuration as a Function of the Fuse Settings of WDTON” on page 60
Table 29-5 on page 198
Bit No
0
7
6
5
4
3
2
1
Bit No
7
6
6
4
3
2
1
0
Description
-
-
-
-
-
-
-
Self-Programming Enable
Description
External Reset disable
DebugWIRE Enable
Enable Serial Program and Data
Downloading
Watchdog Timer always on
EEPROM memory is preserved through
the Chip Erase
Brown-out Detector trigger level
Brown-out Detector trigger level
Brown-out Detector trigger level
180.
for BODLEVEL Fuse decoding.
Table 28-4 on page 181
for description of RSTDISBL and DWEN
Default Value
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
to
Table 28-5 on page 182
Default Value
1 (unprogrammed)
1 (unprogrammed)
0 (programmed, SPI
prog. enabled)
1 (unprogrammed)
1 (unprogrammed,
EEPROM not
preserved)
1 (unprogrammed)
1 (unprogrammed)
1 (unprogrammed)
“Program And Data
ATA8742
for
181