Meadow.Foundation.ICs.IOExpanders.Sc16is752

Sc16is752
Status
Source code	GitHub
Datasheet(s)	GitHub
NuGet package

Code Example

private Sc16is752? _expander = null;

private ISerialPort? _expanderPort = null;
private ISerialPort? _nativePort = null;

private const int Rate = 9600;

public override async Task Initialize()
{
    // NOTE: This sample connects PortA on the expander back to COM1 on the F7Feather
    Resolver.Log.Info("Initialize...");

    var address = Sc16is7x2.Addresses.Address_0x4D;

    try
    {
        _expander = new Sc16is752(
            Device.CreateI2cBus(),
            new Meadow.Units.Frequency(1.8432, Meadow.Units.Frequency.UnitType.Megahertz),
            address);

        _expanderPort = _expander.PortA.CreateSerialPort(Rate);
        _nativePort = Device.PlatformOS.GetSerialPortName("com1")?.CreateSerialPort(Rate);
    }
    catch (Exception ex)
    {
        Resolver.Log.Error($"Failed to initialize 0x{(byte)address:X2}: {ex.Message}");
        await Task.Delay(1000);
    }
}

public override Task Run()
{
    if (_expander == null || _expanderPort == null || _nativePort == null)
    {
        return Task.CompletedTask;
    }

    Task.Run(() => PingReply(_expanderPort, _nativePort));

    while (true)
    {
        Thread.Sleep(1000);
    }
}

private async Task PingReply(ISerialPort portA, ISerialPort portB)
{
    var readBuffer = new byte[64];

    Resolver.Log.Info("Opening ports...");
    portA.Open();
    portB.Open();

    var abMessage = "ping\n";
    var baMessage = "reply\n";
    var count = 0;

    while (true)
    {
        try
        {
            // A -> B
            Resolver.Log.Info($"TEST A->B");
            var messageAB = Encoding.ASCII.GetBytes(abMessage);
            Resolver.Log.Info($"Writing {messageAB.Length} bytes on A...");
            Resolver.Log.Info($"  {BitConverter.ToString(messageAB)}");

            portA.Write(messageAB);

            Resolver.Log.Info($"Reading on B...");
            count = 0;
            while (count < messageAB.Length)
            {
                count += portB.Read(readBuffer, count, messageAB.Length);
            }

            Resolver.Log.Info($"Read {count} bytes on B");
            Resolver.Log.Info($"  {BitConverter.ToString(readBuffer, 0, count)}");

            var rxString = Encoding.ASCII.GetString(readBuffer, 0, count);
            Resolver.Log.Info($"A sent: {abMessage}");
            Resolver.Log.Info($"B received: {rxString}\n");


            // B -> A
            Resolver.Log.Info($"TEST B->A");
            var messageBA = Encoding.ASCII.GetBytes(baMessage);
            Resolver.Log.Info($"Responding with {messageBA.Length} bytes on B...");
            Resolver.Log.Info($"  {BitConverter.ToString(messageBA)}");

            portB.Write(messageBA);
            Resolver.Log.Info($"Reading on A...");
            count = 0;
            while (count < messageBA.Length)
            {
                count += portA.Read(readBuffer, count, messageBA.Length);
            }

            Resolver.Log.Info($"Read {count} bytes on A");
            Resolver.Log.Info($"  {BitConverter.ToString(readBuffer, 0, count)}");

            rxString = Encoding.ASCII.GetString(readBuffer, 0, count);
            Resolver.Log.Info($"B sent: {baMessage}");
            Resolver.Log.Info($"A received: {rxString}\n");


            await Task.Delay(30000);
        }
        catch (Exception ex)
        {
            Resolver.Log.Error($"Test error: {ex.Message}");
            await Task.Delay(5000);
        }
    }
}

Sample project(s) available on GitHub