从 arduino 获取串行输出的奇怪行为

Question

我制作了一个 Arduino 脚本，用于在按下按钮时打印按键：

#include <Keypad.h>

//Buttons
const byte ROWS = 2;
const byte COLS = 2;
char keys[ROWS][COLS] = {
    {'1','2'},
    {'3','4'}
};
byte rowPins[ROWS] = {A0, A1};
byte colPins[COLS] = {30, 31};
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );

void setup() {
    Serial.begin(9600);
    keypad.addEventListener(keypadEvent);
}

void loop() {
    char key = keypad.getKey();
}

void keypadEvent(KeypadEvent key){
    switch (keypad.getState()){
        case PRESSED:
            Serial.println(key);
            break;
        default:
            break;
    }
}

然后，我制作了一个 C# 代码，用于在调试控制台中打印它（在继续之前进行测试）：

using System;
using System.Diagnostics;
using System.IO.Ports;

namespace ConsoleApplication1
{
    class Program
    {
        public static void Main()
        {
            SerialPort SP = new SerialPort("COM3");

            SP.BaudRate = 9600;
            SP.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);

            SP.Open();
            Console.WriteLine("Press any key to continue...");
            Console.WriteLine();
            Console.ReadKey();
            SP.Close();
        }

        private static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
        {
            SerialPort SP = (SerialPort)sender;
            string msg = SP.ReadExisting();
            Debug.Print($"Data Received: {msg}");
        }
    }
}

当使用 Arduino 的串行监视器时，我得到了良好的行为：

但是在使用我的控制台应用程序时，有时会出现空行：

关于如何改进它有什么想法吗？

Answer 1

Jasc24 让我上路了。 SerialPort.ReadExisting() 读取一个可能未完成的流，并且 SerialDataReceivedEventHandler 可以为一行触发多次。

我的解决方法如下：

class Program
{
    static string line = string.Empty;

    public static void Main()
    {
        SerialPort SP = new SerialPort("COM3");

        SP.BaudRate = 9600;
        SP.DataReceived += new SerialDataReceivedEventHandler(DataReceivedHandler);

        SP.Open();
        Console.WriteLine("Press any key to continue...");
        Console.WriteLine();
        Console.ReadKey();
        SP.Close();
    }

    private static void DataReceivedHandler(object sender, SerialDataReceivedEventArgs e)
    {
        SerialPort SP = (SerialPort)sender;
        line = $"{line}{SP.ReadExisting()}";
        if (line.Contains(Environment.NewLine))
        {
            line = line.Replace(Environment.NewLine, string.Empty);
            Debug.Print($"Data Received: {line}");
            line = string.Empty;
        }            
    }
}

等待 EOL 字符以确保在打印之前我得到了所有行。

从 arduino 获取串行输出的奇怪行为

Strange behavior on getting serial outputs from arduino

c#

serial-port

arduino