31.3.1 Initialization

To operate the DAC, the following steps are required:

  • Select the DAC reference voltage in the Voltage Reference (VREF) peripheral by writing the DAC and AC Reference Selection bits (DAC0REFSEL) in the Control A register of the Voltage Reference (VREF.CTRLA) for DAC0. For DAC1, use DAC1REFSEL in VREF.CTRLC. For DAC2, use DAC2REFSEL in VREF.CTRLD.
  • The conversion range is between GND and the selected reference voltage.
  • Configure the further usage of the DAC output:
    • Configure an internal peripheral (e.g. AC, ADC) to use the DAC output. See the according peripheral's documentation.
    • Enable the output to a pin by writing a '1' to the Output Enable bit (OUTEN) in the Control A register (DAC.CTRLA). This requires configuration of the Port peripheral.

    For DAC0, either one or both options are valid. Other instances of the DAC only support internal signaling.

  • Write an initial digital value to the Data register (DAC.DATA).
  • Enable the DAC by writing a '1' to the ENABLE bit in the Control A register (DAC.CTRLA).