Meadow.Foundation.ICs.IOExpanders.Pcf8574

Pcf8574
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

Code Example

private Pcf8574 device;

public override Task Initialize()
{
    device = new Pcf8574(Device.CreateI2cBus(1), 0x20, Device.Pins.D01);

    return base.Initialize();
}

public override Task Run()
{
    TestDigitalOutputPorts(10);

    return Task.CompletedTask;
}

private void TestDigitalOutputPorts(int loopCount)
{
    var out00 = device.CreateDigitalOutputPort(device.Pins.P0);
    var out01 = device.CreateDigitalOutputPort(device.Pins.P1);
    var out02 = device.CreateDigitalOutputPort(device.Pins.P2);
    var out03 = device.CreateDigitalOutputPort(device.Pins.P3);
    var out04 = device.CreateDigitalOutputPort(device.Pins.P4);
    var out05 = device.CreateDigitalOutputPort(device.Pins.P5);
    var out06 = device.CreateDigitalOutputPort(device.Pins.P6);
    var out07 = device.CreateDigitalOutputPort(device.Pins.P7);

    var outputPorts = new List<IDigitalOutputPort>()
    {
        out00, out01, out02, out03,
        out04, out05, out06, out07,
    };

    foreach (var outputPort in outputPorts)
    {
        outputPort.State = true;

        Thread.Sleep(1000);
    }

    for (int l = 0; l < loopCount; l++)
    {
        // loop through all the outputs
        for (int i = 0; i < outputPorts.Count; i++)
        {
            // turn them all off
            device.AllOff();

            Thread.Sleep(1000);

            // turn them all on
            device.AllOn();
            Thread.Sleep(1000);

            // turn on just one
            Resolver.Log.Info($"Update pin {i} to {true}");
            outputPorts[i].State = true;
            Thread.Sleep(250);

            // turn off just one
            Resolver.Log.Info($"Update pin {i} to {false}");
            outputPorts[i].State = false;
            Thread.Sleep(250);
        }
    }

    // cleanup
    for (int i = 0; i < outputPorts.Count; i++)
    {
        outputPorts[i].Dispose();
    }
}

Sample project(s) available on GitHub

Class Pcf8574

Represents the Pcf8574 8-bit I/O I2C expander

Assembly: Pcx857x.dll

View Source

Declaration

public class Pcf8574 : Pcx8574, IDigitalOutputController, IDigitalInputController, IDigitalInterruptController, IPinController, II2cPeripheral, IDisposable

Inheritance: System.Object -> Meadow.Foundation.ICs.IOExpanders.Pcx857x

Implements:
Meadow.Hardware.IDigitalOutputController, Meadow.Hardware.IDigitalInputController, Meadow.Hardware.IDigitalInterruptController, Meadow.Hardware.IPinController, Meadow.Hardware.II2cPeripheral, System.IDisposable

Methods

GetAddressForPins(bool, bool, bool)

Helper method to get address from address pin configuration

View Source

Declaration

public static byte GetAddressForPins(bool pinA0, bool pinA1, bool pinA2)

Returns

System.Byte: The device address

Parameters

Type	Name	Description
System.Boolean	pinA0	State of A0 address pin - true if high
System.Boolean	pinA1	State of A1 address pin - true if high
System.Boolean	pinA2	State of A2 address pin - true if high

Implements

• Meadow.Hardware.IDigitalOutputController
• Meadow.Hardware.IDigitalInputController
• Meadow.Hardware.IDigitalInterruptController
• Meadow.Hardware.IPinController
• Meadow.Hardware.II2cPeripheral
• System.IDisposable