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# 1.7 DAC Waveform Generation

This example application shows how to use the DAC to generate a 1 kHz Sine or Sawtooth wave with a look up table.

## Description

This example application shows how to use the DAC Peripheral library to generate a 1 kHz Sine or Sawtooth wave with look up table. DAC starts conversion on a trigger from a timer period interrupt configured to occur at every 10 microseconds. In this application, the number of the DAC samples in a look up table is 100.

## Downloading and Building the Application

To clone or download this application from Github, go to the main page of this repository and then click Clone button to clone this repository or download as zip file. This content can also be downloaded using content manager by following these instructions.

Path of the application within the repository is apps/dac/dac_wav_gen/firmware.

To build the application, refer to the following table and open the project using its IDE.

Project Name | Description
--- | ---
sam_d21_xpro.X | MPLABX project for SAM D21 Xplained Pro Evaluation Kit
sam_da1_xpro.X | MPLABX project for SAM DA1 Xplained Pro Evaluation Kit

## Setting Up the Hardware

The following table shows the target hardware for the application projects.

Project Name | Description
--- | ---
sam_d21_xpro.X | SAM D21 Xplained Pro Evaluation Kit
sam_da1_xpro.X | SAM DA1 Xplained Pro Evaluation Kit

### Setting Up SAM D21 Xplained Pro Evaluation Kit

- Connect an oscilloscope to monitor DAC pin PA02 (Pin 3 of the EXT3 header)
- Connect the Debug USB port on the board to the computer using a micro USB cable

### Setting Up SAM DA1 Xplained Pro Evaluation Kit

- Connect an oscilloscope to monitor DAC pin PA02 (Pin 3 of the EXT3 header)
- Connect the Debug USB port on the board to the computer using a micro USB cable

## Running the Application

1. Build and Program the application using its IDE
2. Observe a sine wave of 1 kHz frequency on DAC output pins
3. Press switch to toggle the waveform shape from sine wave to sawtooth wave and back
4. Refer to the below table for DAC output pin and switch details:

   Board | DAC Output Pin | Switch Name
   --- | --- | ---
   SAM D21 Xplained Pro Evaluation Kit | PA02 (Pin 3 of the EXT3 header) | SW0
   SAM DA1 Xplained Pro Evaluation Kit | PA02 (Pin 3 of the EXT3 header) | SW0