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1 dala = 0, 2 dala = 1 – Rainbow Electronics ATmega64C1 User Manual

Page 269

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269

7647A–AVR–02/08

ATmega32/64/M1/C1

• Bit 2 – DALA: Digital to Analog Left Adjust

Set this bit to left adjust the DAC input data.
Clear it to right adjust the DAC input data.
The DALA bit affects the configuration of the DAC data registers. Changing this bit affects the
DAC output on the next DACH writing.

• Bit 1 – DAOE: Digital to Analog Output Enable bit

Set this bit to output the conversion result on D2A,
Clear it to use the DAC internally.

• Bit 0 – DAEN: Digital to Analog Enable bit

Set this bit to enable the DAC,
Clear it to disable the DAC.

21.4.2

Digital to Analog Converter input Register – DACH and DACL

DACH and DACL registers contain the value to be converted into analog voltage.

Writing the DACL register prohibits the update of the input value until DACH has not been writ-
ten too. So the normal way to write a 10-bit value in the DAC register is firstly to write DACL the
DACH.

In order to work easily with only 8 bits, there is the possibility to left adjust the input value. Like
this it is sufficient to write DACH to update the DAC value.

21.4.2.1

DALA = 0

21.4.2.2

DALA = 1

1

0

0

Timer/Counter0 Overflow

1

0

1

Timer/Counter1 Compare Match B

1

1

0

Timer/Counter1 Overflow

1

1

1

Timer/Counter1 Capture Event

Table 1. DAC Auto Trigger source selection (Continued)

DATS2

DATS1

DATS0

Description

Bit

7

6

5

4

3

2

1

0

-

-

-

-

-

-

DAC9

DAC8

DACH

DAC7

DAC6

DAC5

DAC4

DAC3

DAC2

DAC1

DAC0

DACL

Read/Write

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Initial Value

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

Bit

7

6

5

4

3

2

1

0

DAC9

DAC8

DAC7

DAC6

DAC5

DAC4

DAC3

DAC2

DACH

DAC1

DAC0

-

-

-

-

-

-

DACL

Read/Write

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

R/W

Initial Value

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0