DAC Interface¶

Note

The Digital-Analog converter allows applying of a specific voltage to a Pin to, for example generate an analog audio signal.

Simple Usage¶

DACs in libyggdrasil can be used as if they were normal variables. Writing a floating point value between 0 and 1 to it will cause a voltage between 0V and the reference voltage to be applied to the DAC pin. Reading will read back the current value stored in the DAC.

The following code will apply 2V to the DAC A header.

const double ReferenceVoltage = 3.3;

yggdrasil_DAC_Write(DACA, 2.0 / ReferenceVoltage);

constexpr auto ReferenceVoltage = 3.3;

bsp::DACA = 2.0 / ReferenceVoltage;

Available Pins¶

Name	Description
DACA	Analog Header DAC A
DACB	Analog Header DAC B

Custom DAC¶

In order to apply a voltage to a DAC pin that has not been pre-defined by libyggdrasil, first it needs to be properly configured through the project’s .ioc file. Once this is done, the new DAC can be defined like this:

dac_t MyDAC = { &hdac, 1 };

using DAConverter2 = bsp::drv::DAConverter<&hdac2, bsp::mid::drv::DACChannel>;

static constexpr auto &MyDAC = DAConverter2::Channel<1>;

and then used like all other DACs.

yggdrasil_DAC_Write(MyDAC, 0.5 / ReferenceVoltage);

MyDAC = 0.5 / ReferenceVoltage;