Digital-to-Analog Converter (DAC)

Overview

This sample demonstrates how to use the DAC driver API.

Building and Running

The DAC output is defined in the board’s devicetree and pinmux file.

The board’s /zephyr,user node must have dac, dac-channel-id, and dac-resolution properties set. See the predefined overlays in samples/drivers/dac/boards for examples.

Building and Running for ST Nucleo L073RZ

The sample can be built and executed for the ST Nucleo L073RZ as follows:

west build -b nucleo_l073rz samples/drivers/dac
west flash

Building and Running for ST Nucleo L152RE

The sample can be built and executed for the ST Nucleo L152RE as follows:

west build -b nucleo_l152re samples/drivers/dac
west flash

Building and Running for ST Nucleo F767ZI

The sample can be built and executed for the ST Nucleo F767ZI as follows:

west build -b nucleo_f767zi samples/drivers/dac
west flash

Building and Running for ST Nucleo F429ZI

The sample can be built and executed for the ST Nucleo F429ZI as follows:

west build -b nucleo_f429zi samples/drivers/dac
west flash

Building and Running for NXP TWR-KE18F

The sample can be built and executed for the NXP TWR-KE18F as follows:

west build -b twr_ke18f samples/drivers/dac
west flash

DAC output is available on pin A32 of the primary TWR elevator connector.

Building and Running for NXP FRDM-K64F

The sample can be built and executed for the NXP FRDM-K64F as follows:

west build -b frdm_k64f samples/drivers/dac
west flash

DAC output is available on connector J4 pin 11.

Building and Running for BL652

The BL652 DVK PCB contains a footprint for a MCP4725 to use as an external DAC. Note this is not populated by default. The sample can be built and executed for the Laird Connectivity BL652 DVK as follows:

west build -b bl652_dvk samples/drivers/dac
west flash

DAC output is available on pin 1 of the MCP4725.

Building and Running for BL653

The BL653 DVK PCB contains a footprint for a MCP4725 to use as an external DAC. Note this is not populated by default. The sample can be built and executed for the Laird Connectivity BL653 DVK as follows:

west build -b bl653_dvk samples/drivers/dac
west flash

DAC output is available on pin 1 of the MCP4725.

Building and Running for BL654

The BL654 DVK PCB contains a footprint for a MCP4725 to use as an external DAC. Note this is not populated by default. The sample can be built and executed for the Laird Connectivity BL654 DVK as follows:

west build -b bl654_dvk samples/drivers/dac
west flash

DAC output is available on pin 1 of the MCP4725.

Sample output

You should see a sawtooth signal with an amplitude of the DAC reference voltage and a period of approx. 4 seconds at the DAC output pin specified by the board.

The following output is printed:

Generating sawtooth signal at DAC channel 1.

Note

If the DAC is not supported, the output will be an error message.