模拟串口收发数据

Question

我写了这段代码来模拟应用程序的串口读写。

我想每3毫秒发送一次数据，在发送之前，我将数据记录到一个图表和一个文件中。另外，在发送数据之后，将调用DataRecieved函数在图表上描述数据并将数据记录到文件中。

但是当我执行它时，在某些点上会显示错误的结果，而且它也不能每3毫秒执行一次。(有时每6毫秒，...，输出和输入的文件会被附加)

此外，它有时会在我写入文件行中抛出以下错误：

对象引用未设置为对象的实例。

我能做些什么来解决这个问题？

class SignalControllerSimulator
{
       public SignalControllerSimulator(SignalReaderSimulator reader, SignalWriterSimulator writer, LineSeries PitchInputLine, LineSeries RollInputLine, LineSeries YawInputLine, LineSeries PitchOutputLine, LineSeries RollOutputLine, LineSeries YawOutputLine)
       {
             ....
              //do some initialization

           SentFileLogger = new WriteFileLogger(SentFolderName);
           RecFileLogger = new ReadFileLogger(RecFolderName);
           SentFileLogger.Open(true);
           RecFileLogger.Open(true);

           rampTime = SenarioTime = SineTime = StepTime = 320;//1000ms
           reader.DataReceived += DataReceived;
       }
    #region readSection
    ObservableCollection<ChartItem> PitchInputItems = new ObservableCollection<ChartItem>();
    ObservableCollection<ChartItem> RollInputItems = new ObservableCollection<ChartItem>();
    ObservableCollection<ChartItem> YawInputItems = new ObservableCollection<ChartItem>();

    int PitchIndex = 1; int RollIndex = 1; int YawIndex =1 ;

    public void DataReceived(ReadSignal signal)
    {

        this.PitchInputLine.Dispatcher.Invoke(new Action(() =>   
        {
            PitchInputItems.Add(new ChartItem(signal.PitchLocation, PitchIndex++)); 
            RollInputItems.Add(new ChartItem(signal.RollLocation,  RollIndex++));              
            YawInputItems.Add(new ChartItem(signal.YawLocation, YawIndex++));
            PitchInputLine.ItemsSource = PitchInputItems;
            RollInputLine.ItemsSource = RollInputItems;
            YawInputLine.ItemsSource = YawInputItems;
        }));
            RecFileLogger.Write(true, signal.PitchLocation, signal.RollLocation, signal.YawLocation, DateTime.Now.ToString("h:m:s:fff"));

    }

    public void Stop()
    {
      ...
    }
    #endregion
    #region writeSection

    public void StartSendingLocations()
    {

        EndIndex = setEndIndex();
        timer = new System.Timers.Timer(interval);
        timer.Elapsed += new System.Timers.ElapsedEventHandler(timer_Elapsed);
        timer.Start();
    }
    void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {
        if (Index>=EndIndex)
        {
            Stop();
            return;
        }
         ...
        // some switch case and function calling...
            CreateCommand();
        //setting reader settings


            //log to file the data sent:
            SentFileLogger.Write(true, writer.WSignal.PitchLocation,                           writer.WSignal.PitchAngularVelocity, writer.WSignal.RollLocation,
                    writer.WSignal.RollAngularVelocity, writer.WSignal.YawLocation, writer.WSignal.YawAngularVelocity,
                    DateTime.Now.ToString("h:m:s:fff"));
            SignalWriter_DataSent(writer.WSignal);
            TimeWriter.WriteLine("end:------------>" + DateTime.Now.ToString("h:m:s:fff"));
            TimeWriter.WriteLine();

            reader.ThreadMain(reader.RSignal);


            Index++;
    }

    ObservableCollection<ChartItem> PitchOutputItems = new ObservableCollection<ChartItem>();
    ObservableCollection<ChartItem> RollOutputItems = new ObservableCollection<ChartItem>();
    ObservableCollection<ChartItem> YawOutputItems = new ObservableCollection<ChartItem>();

    int PitchIndex1 = 1; int RollIndex1 = 1; int YawIndex1 = 1;

    void SignalWriter_DataSent(WriteSignal signal)
    {
        RollInputLine.Dispatcher.Invoke(new Action(() =>
        {
            PitchOutputItems.Add(new ChartItem(signal.PitchLocation, PitchIndex1++)); //PitchOutputItems.Add(new ChartItem(signal.PitchLocation, interval * PitchIndex1++));
            RollOutputItems.Add(new ChartItem(signal.RollLocation,RollIndex1++)); //RollOutputItems.Add(new ChartItem(signal.RollLocation, interval * RollIndex1++));
            YawOutputItems.Add(new ChartItem(signal.YawLocation,YawIndex1++)); //YawOutputItems.Add(new ChartItem(signal.YawLocation, interval * YawIndex1++));
            PitchOutputLine.ItemsSource = PitchOutputItems;
            RollOutputLine.ItemsSource = RollOutputItems;
            YawOutputLine.ItemsSource = YawOutputItems;
        }));
    }

    private int setEndIndex()
    {
        return EndTime / interval;
    }

}

附加文件：

data Receiving file

data sending file

time between sendings

Answer 1

您将无法从.NET计时器获得3毫秒的分辨率。例如，请参阅Why are .NET timers limited to 15 ms resolution?。

你可以使用一个专门的线程来产生Thread.Sleep (精度也不是很高)，或者如果精度真的很重要的话，也可以使用Thread.SpinWait。