Question

我目前正在使用一种名为Fluke 5500A多产品校准设备的设备。我在C＃中编写了一个小程序来与它进行交互，并了解它的工作原理，但不幸的是，SerialPort.DataReceived给了我一些非常奇怪的结果。该计划不长，所以我将在这里全文发布：

class Program
{
    static public bool isExecuting = true;
    static private string serialCommand;
    static private string dataReceived;

    static void Main(string[] args)
    {
        SerialPortConnection serialPort = new SerialPortConnection();

        serialPort.OpenSerialConnection();

        while (isExecuting == true)
        {
            Console.WriteLine("Enter a command or type q to quit.");
            serialCommand = Console.ReadLine().ToUpper();

            if (serialCommand == "Q")
                isExecuting = false;
            else if (serialCommand == "CLEAR")
                Console.Clear();
            else
            {
                dataReceived = serialPort.WriteSerialConnection(serialCommand);
                Console.WriteLine(dataReceived);
            }
        }

        serialPort.CloseSerialConnection();
    }
}

}

我的SerialPortConnection类：

public class SerialPortConnection
{
    private SerialPort serialPort;
    private string dataReceived = "none";

    public SerialPortConnection(string comPort = "Com3", int baud = 9600, System.IO.Ports.Parity parity = System.IO.Ports.Parity.None, int dataBits = 8, System.IO.Ports.StopBits stopBits = System.IO.Ports.StopBits.One)
    {
        serialPort = new SerialPort(comPort, baud, parity, dataBits, stopBits);
    }

    public void OpenSerialConnection()
    {
        try
        {
            serialPort.Open();
        }
        catch (Exception e)
        {
            Console.Write("\nError");
            Console.Write(e);
        }
    }

    public string WriteSerialConnection(string SerialCommand)
    {
        try
        {
            serialPort.Write(String.Format(SerialCommand + "\r"));
            dataReceived = serialPort.ReadExisting();
            return dataReceived;
        }
        catch (Exception e)
        {
            Console.Write("\nError");
            Console.Write(e);
            return "Execution Unsuccessful";
        }
    }

    public void CloseSerialConnection()
    {
        try 
        {
            serialPort.Close();
        }
        catch (Exception e)
        {
            Console.Write("\nError");
            Console.Write(e);
        }
    }
}

我目前的问题是控制台的输出如下所示：

Enter a command or type q to quit.
*IDN?

Enter a command or type q to quit.
OUT 50V <-- Command input
*IDN? <-- Previous command echoed back
FLUKE,5500A,8030005,2.61+1.3+2.0+* <-- Data received from previous command
161>
Enter a command or type q to quit.
OPER
OUT 50V
162>
Enter a command or type q to quit.
STBY
OPER
163>
Enter a command or type q to quit.
*RST
STBY
164>
Enter a command or type q to quit.

命令执行得很好但是控制台的输出似乎是最后执行的命令以及该命令返回的任何数据。我不知道为什么会这样。

编辑：

感谢Robert P的回答，我实现了以下代码：

var received = "";
bool isReading = true;
while (isReading == true)
{
    try
    {
        received += serialPort.ReadExisting();
        if (received.Contains('>'))
            isReading = false;
    }
    catch (Exception e)
    {
    }
}
Console.WriteLine(received);

Answer 1

您的问题的一部分是串行通信远非瞬间。 .ReadExisting()方法从SerialPort对象的缓冲区中提取数据，但没有做任何事情来确保设备已完成发出命令。可以这样想：

+----+            +----------+           +------------+
|Your|--Command-->|Serial    |---UART--->|    Device  |
|Code|            |Port Obj  |           |            |
+----+            +----------+           +------------+

+----+            +----------+           +------------+
|Your|<--Read-----|Serial    |           |Device      |
|Code| (is empty) |          |           |(processing)|
+----+            +----------+           +------------+

+----+            +----------+           +------------+
|Your|            |Serial    |<-response-|Device      |
|Code|            |(has data)|           |(responding)|
+----+            +----------+           +------------+

+----+            +----------+           +------------+
|Your|--Command2->|Serial    |---UART--->|    Device  |
|Code|            |(has data)|           |            |
+----+            +----------+           +------------+

+----+            +----------+           +------------+
|Your|<--Read-----|Serial    |           |Device      |
|Code| (previous  |          |           |(processing)|
+----+  response) +----------+           +------------+

相反，在发送下一个命令之前，查找模式，标记或其他识别标记以了解传输已完成。继续阅读（期待超时 - 他们被抛出作为例外！）直到你知道你收到了整个回复。在这种情况下，可能是>字符表示“准备好更多输入”。您可以将其解释为“响应已完成。”

SerialPort.DataReceived返回奇怪的结果

1 个答案: