13.3 DAC Synchronous Driver

The functions in Digital-to-Analog Converter (DAC) synchronous driver will block (i.e. not return) until the operation is done.

The dac_sync_write function will perform a conversion of digital value to analog voltage and return the result when it is ready.

Summary of the API's Functional Features

The API provides functions to:

  • Initialize and deinitialize the driver and associated hardware

  • Enable and disable the DAC channel

  • Write buffers with multiple digital data to DAC

Summary of Configuration Options

Below is a list of the main DAC parameters that can be configured in START. Many of these parameters are used by the dac_sync_init function when initializing the driver and underlying hardware.

  • Select which DAC output signals to be enabled

  • Which clock source and prescaler the DAC uses

  • Reference voltage selection

  • Run in Standby or Debug mode

Driver Implementation Description

In DAC synchronous driver, new digital values will be written directly to the DAC hardware and returned when all digital data has been converted.

Example of Usage

The following shows a simple example of using the DAC. The DAC must have been initialized by dac_sync_init. This initialization will configure the operation of the DAC, such as reference voltage, etc.

The example enables channel 0 of DAC0, and finally starts a D/A conversion to output a waveform.

          /**
           * Example of using DAC_0 to generate waveform.
           */
          void DAC_0_example(void)
          {
              uint16_t i = 0;
              dac_sync_enable_channel(&DAC_0, 0);
              for(;;) {
                  dac_sync_write(&DAC_0, 0, &i, 1);
                  i = (i+1) % 1024;
              }
          }

Dependencies

  • The DAC peripheral and its related I/O lines and clocks