This Arduino library provides an interface for the AD74412R & AD74413R chips from Analog Devices (does not support HART functionality on AD74413R). It is based on the original C library provided by Analog Devices but has been adapted and enhanced for the Arduino environment.

This version is easier to use compared to the original AD library:

• User-friendly methods for accessing chip parameters and converting real ADC/DAC values & units
• Automatic ADC polling & status update is done in the background, by calling the poll() method in the user program's main loop for non-blocking operation (especially effective when combined with continuous ADC reading mode)
• ADC function & conversion mode changes are fully implemented as recommended in the chip's datasheet
• MUX register settings have been modified in output modes (voltage or current) to provide real output voltage/current feedback
• The 200K pull-down resistor is automatically enabled depending on the ADC function, as recommended in the chip's datasheet

Include the library in your sketch, make sure you're using SPI as well:

#include <ad7441xr.h>
#include <SPI.h>

Initialize the AD7441XR object:

AD7441XR ad7441xr(CS_PIN, SPI, AD74412R);

In your setup() function, initialize SPI and the chip:

SPI.begin(SPI_SCK, SPI_MISO, SPI_MOSI);
digitalWrite(AD7441XR_CS_PIN, HIGH);
ad7441xr.begin();

In your loop() function, call the poll() method to automatically update ADC values:

ad7441xr.poll();

You can call several methods to enable & set channels, either in loop() or in setup().

// Enable channels A & B
swio.enableChannel(AD7441XR_CH_A, true);
swio.enableChannel(AD7441XR_CH_B, true);

// Set channel functions to AI and AO
swio.setChannelFunc(AD7441XR_CH_A, AD7441XR_VOLTAGE_IN);
swio.setChannelFunc(AD7441XR_CH_B, AD7441XR_VOLTAGE_OUT);

// Start ADC continuous reading (put in setup())
swio.setAdcMode(AD7441XR_START_CONT);

// Set DAC to 3.14V on channel B = index 1
swio.setDac(1, 3.14);

If your poll() function is executed frequently, and the chip is set in continuous ADC reading mode, ADC values can be accessed at any point of the code with get methods :

float adcValue = swio.getAdc(i);    // ADC value
int adcUnit = swio.getAdcUnit(i);   // ADC unit code (1=V, 2=mA...)

Refer to the ad7441xr.h file to get the complete list of public methods included in the library.

This library is released under the MIT License.

Contributions to this library are welcome. Please submit pull requests or open issues on the GitHub repository.

This library is based on the original C library provided by Analog Devices.