ATtiny26(L)

Fuse Bits

The ATtiny26 has two Fuse bytes. Table 49 and Table 50 describe briefly the functional-

ity of all the fuses and how they are mapped into the fuse bytes. Note that the fuses are

Fuse High Byte

Bit No

Description

Default Value

7

–

1

(unprogrammed)

6

–

1

(unprogrammed)

5

–

1

(unprogrammed)

RSTDISBL

4

Select if PB7 is I/O pin or

1

(unprogrammed, PB7 is

RESET pin

RESET pin)

SPIEN(1)

3

Enable Serial Program

0

(programmed, SPI prog.

and Data Downloading

enabled)

EEPROM memory is

1

(unprogrammed, EEPROM not

EESAVE

2

preserved through the Chip

preserved)

Erase

BODLEVEL

1

Brown out detector trigger

1

(unprogrammed)

level

BODEN

0

1

(unprogrammed, BOD

Brown out detector enable

disabled)

Note: 1. The SPIEN Fuse is not accessible in serial programming mode.

Table 50. Fuse Low Byte

Fuse Low Byte

Bit No

Description

Default Value

PLLCK

7

Use PLL for internal clock

1

(unprogrammed)

CKOPT(3)

6

Oscillator options

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

0

(programmed)(2)

CKSEL0

0

Select Clock source

1

(unprogrammed)(2)