Meadow.Foundation.Sensors.LoadCell.Nau7802 2.0.1.2

Meadow.Foundation.Sensors.LoadCell.Nau7802

NAU7802 I2C 24-Bit dual channel analog to digital converter

The Nau7802 library is included in the Meadow.Foundation.Sensors.LoadCell.Nau7802 nuget package and is designed for the Wilderness Labs Meadow .NET IoT platform.

This driver is part of the Meadow.Foundation peripherals library, an open-source repository of drivers and libraries that streamline and simplify adding hardware to your C# .NET Meadow IoT applications.

For more information on developing for Meadow, visit developer.wildernesslabs.co.

To view all Wilderness Labs open-source projects, including samples, visit github.com/wildernesslabs.

Installation

You can install the library from within Visual studio using the the NuGet Package Manager or from the command line using the .NET CLI:

dotnet add package Meadow.Foundation.Sensors.LoadCell.Nau7802

Usage

private Nau7802 loadSensor;

public int CalibrationFactor { get; set; } = 16526649; // TODO: change this based on your scale (using the method provided below)
public Mass CalibrationWeight { get; set; } = new Mass(1600, Mass.UnitType.Grams); // TODO: enter the known-weight you used in calibration

public override async Task Initialize()
{
    Resolver.Log.Info("Initialize...");

    loadSensor = new Nau7802(Device.CreateI2cBus());

    if (CalibrationFactor == 0)
    {
        await GetAndDisplayCalibrationUnits(loadSensor);
    }
    else
    {   // wait for the ADC to settle
        await Task.Delay(500);

        // Set the current load to be zero
        loadSensor.SetCalibrationFactor(CalibrationFactor, CalibrationWeight);
        loadSensor.Tare();
    }

    loadSensor.Updated += (sender, values) => Resolver.Log.Info($"Mass is now returned {values.New.Grams:N2}g");
}

public override Task Run()
{
    loadSensor.StartUpdating(TimeSpan.FromSeconds(2));

    return Task.CompletedTask;
}

public async Task GetAndDisplayCalibrationUnits(Nau7802 sensor)
{
    // first notify the user we're starting
    Resolver.Log.Info($"Beginning Calibration. First we'll tare (set a zero).");
    Resolver.Log.Info($"Make sure scale bed is clear. Next step in 5 seconds...");

    await Task.Delay(5000);
    sensor.Tare();
    Resolver.Log.Info($"Place a known weight on the scale. Next step in 5 seconds...");

    await Task.Delay(500);
    var factor = sensor.CalculateCalibrationFactor();

    Resolver.Log.Info($"Your scale's Calibration Factor is: {factor}. Enter this into the code for future use.");
}

How to Contribute

• Found a bug? Report an issue
• Have a feature idea or driver request? Open a new feature request
• Want to contribute code? Fork the Meadow.Foundation repository and submit a pull request against the develop branch

Need Help?

If you have questions or need assistance, please join the Wilderness Labs community on Slack.

About Meadow

Meadow is a complete, IoT platform with defense-grade security that runs full .NET applications on embeddable microcontrollers and Linux single-board computers including Raspberry Pi and NVIDIA Jetson.

Build

Use the full .NET platform and tooling such as Visual Studio and plug-and-play hardware drivers to painlessly build IoT solutions.

Connect

Utilize native support for WiFi, Ethernet, and Cellular connectivity to send sensor data to the Cloud and remotely control your peripherals.

Deploy

Instantly deploy and manage your fleet in the cloud for OtA, health-monitoring, logs, command + control, and enterprise backend integrations.