A Particle library for the DAC121C08X

Ever need to add more than one 12-bit DAC IC's to your board? Or, is the 3.3V max on the on-board DAC not quite what you're looking for? Look no further! Add up to 8 12-bit micropower DAC with an external reference at once using Texas Instruments' DAC121C085 chip!

To hook up, simply grab an 8VSSOP breakout board from Adafruit/Sparkfun/Digikey/Mouser and get started!

Connect the DAC hardware, add the DAC121C08X library to your project and follow this simple example:

#include "DAC121C08X.h"

DAC121C08X dac(0x09);

void setup() {
  dac.begin();
}

void loop() {
  for (int i=0;i<4095;i++) {
    dac.write_value(i);   // Increment the DAC value

    delay(1000);
  }
}

See the examples folder for more details.

There is only one class with two methods in this (ultra) tiny library.

To initialize an instance of the class, the only requirement is the i2c address. For this chip, the available addresses include: 0xA, 0xC, 0xD, 0xE, 0x08, 0x09, 0x4C, 0x4D, and 0x4E. For specific details, check out the datasheet.

Optionally, you can provide the reference voltage you have wired up; the default value is 5V.

To write a specific value, simply provide an unsigned int between 0-4095 for the 12-bit version. Here, 0 will correspond to 0V and 4095 will correspond to [VREF] volts.

Rather than have to calculate the number of bits for the voltage you actually want, use this method to do all the (not very) hard work for you. Simply provide a float between 0 and [VREF] volts.

Here's how you can make changes to this library and eventually contribute those changes back.

To get started, clone the library from GitHub to your local machine.

Change the name of the library in library.properties to something different. You can add your name at then end.

Modify the sources in and with the new behavior.

To compile an example, use particle compile examples/usage command in Particle CLI or use our Desktop IDE.

After your changes are done you can upload them with particle library upload or Upload command in the IDE. This will create a private (only visible by you) library that you can use in other projects. Do particle library add DAC121C08X_myname to add the library to a project on your machine or add the DAC121C08X_myname library to a project on the Web IDE or Desktop IDE.

At this point, you can create a GitHub pull request with your changes to the original library.

If you wish to make your library public, use particle library publish or Publish command.

Copyright 2017 David H Hagan

Licensed under the MIT license