PiJuiceSharp

An implementation of the PiJuice client library based on the original PiJuice Python library in pure .NET. Currently packaged as a .NET 6 library with only a dependency on System.Device.Gpio.

Only a subset of the Status APIs are currently supported, and other APIs such as the RTC and Power Management are not yet implemented. Implementing others should be fairly straightforward, but I just don't have a need for them at the moment - contributions are welcome if you need to extend it!

This library is safe to use even if you don't know that the device will have a PiJuice attached. When a PiJuice isn't present, default values will be returned for all APIs, and a value of NoPiJuice for GetStatus().BatteryStatus.

Installation

You can install the library from NuGet:

dotnet add package PiJuiceSharp

PiJuiceStatus

You can use the PiJuiceStatus class to get various point-in-time status values of the PiJuice board.

To construct a PiJuiceStatus, call PiJuiceStatus.Create(). This returns an implementation of IPiJuiceStatus which will be either a fully connected PiJuiceStatus instance or an AbsentPiJuiceStatus instance which handles the case when no PiJuice was present.

var piJuiceStatus = PiJuiceStatus.Create();

If you're using dependency injection, you can configure the IPiJuiceStatus interface as a singleton:

services.AddSingleton<IPiJuiceStatus>(PiJuiceStatus.Create());

PiJuice Status APIs

GetStatus() returns an object containing basic status information, defined as:

public enum BatteryStatus
    {
        Normal = 0,
        ChargingFromIn = 1,
        ChargingFrom5vIo = 2,
        NotPresent = 3,
        NoPiJuice = 8000
    }

    public enum PowerInputStatus
    {
        NotPresent = 0,
        Bad = 1,
        Weak = 2,
        Present = 3
    }

    public record struct StatusInfo(
      bool IsFault,
      bool IsButton,
      BatteryStatus BatteryStatus,
      PowerInputStatus PowerInput,
      PowerInputStatus PowerInput5vIo);

GetChargeLevel() returns the current charge level of the battery, as a percentage.

GetFaultStatus() returns a dictionary containing the current fault status information of the PiJuice board:

forced_power_off: True

GetBatteryVoltage() returns the current voltage of the battery, in volts.

GetBatteryCurrent() returns the current current of the battery, in amps.

GetBatteryTemperature() returns the current temperature of the battery, in degrees Celsius.

GetIoVoltage() returns the current voltage of the GPIO pins, in volts.

GetIoCurrent() returns the current current of the GPIO pins, in amps.

Working with LEDs

The status API also allows you to read and set the LED colors, including a temporary blinking state.

GetLedState(Led led) returns a Color struct containing the RGB state of either the Led.D1 or Led.D2 LED

SetLedState(Led led, Color color) sets the RGB state of either the Led.D1 or Led.D2 LED to the given Color. (Note that if the LED is not in a user configurable state, this will have no effect.)

GetLedBlinkState(Led led) returns an LedBlinkState struct containing the current blinking state of either the Led.D1 or Led.D2 LED. LedBlinkState is defined as:

public record struct LedBlinkState(byte Count, Color Rgb1, short Period1, Color Rgb2, short Period2);

SetLedBlinkState(Led led, LedBlinkState state) sets the blinking state of either the Led.D1 or Led.D2 LED to the given LedBlinkState. (Note that if the LED is not in a user configurable state, this will have no effect.)

Thread safety

By using a single SemaphoreSlim instance across all instances of PiJuiceInterface, the library guarantees that thread safety is enforced when communicating with the PiJuice.