SerialPort.Open()--IOException - "参数不正确."

Question

我编写了以下代码来配置MainForm加载时的串口.在第一次运行时,它会IOException在端口打开时给出,说明参数不正确.但是,当我重新启动应用程序时,它工作正常.只有在启动计算机后第一次运行应用程序时才会出现异常,然后它才能正常工作,直到下次重新启动计算机.

private void Main_Load(object sender, EventArgs e)
{
    this.serialPort1.PortName = "COM3";
    this.serialPort1.BaudRate = 9600;
    this.serialPort1.DataBits = 8;
    this.serialPort1.DataReceived += new System.IO.Ports.SerialDataReceivedEventHandler(serialPort1_DataReceived);

    this.serialPort1.Open(); //Exception comes here
    this.serialPort1.WriteLine("AT#cid=1" + System.Environment.NewLine);

}

执行细节:

System.IO.IOException未被用户代码处理

Message ="参数不正确.\ r \n"Source ="System"

堆栈跟踪:在System.IO.Ports.InternalResources.WinIOError(的Int32的errorCode,字符串str)在System.IO.Ports.InternalResources.WinIOError()在System.IO.Ports.SerialStream.set_RtsEnable(布尔值)System.IO. Ports.SerialStream..ctor(字符串PORTNAME,的Int32波特率,奇偶校验位,数据位的Int32,停止位停止位,的Int32 readTimeout,的Int32 writeTimeout,握手握手,布尔dtrEnable,布尔rtsEnable,布尔discardNull,字节parityReplace)在System.IO.Ports. SerialPort.Open()在JKamdar.Main.Main_Load(对象发件人,EventArgs e)在d:\项目\ JKamdar\JKamdar\Main.cs:线264处系统System.Windows.Forms.Form.OnLoad(EventArgs的) .Windows.Forms.Form.OnCreateControl()在System.Windows.Forms.Control.CreateControl(布尔fIgnoreVisible)在System.Windows.Forms.Control.CreateControl()在System.Windows.Forms.Control.WmShowWindow(邮件&m)在System.Windows.Forms.Control.WndProc在System.Windows.Forms.ScrollableControl.WndProc在System.Windows(邮件&m)(邮件&m).Forms.ContainerControl.WndProc(消息&m)上System.Windows.Forms.Form.WmShowWindow在System.Windows.Forms.Control.ControlNativeWindow.OnMessage在System.Windows.Forms.Form.WndProc(邮件&m)(邮件&m) (消息&m)上在System.Windows.Forms.NativeWindow.Callback System.Windows.Forms.Control.ControlNativeWindow.WndProc(邮件&m)(IntPtr的的HWND,MSG的Int32,IntPtr的WPARAM,IntPtr的LPARAM)的InnerException:

Answer 1

请尝试使用this.serialPort1.RtsEnable = true

根据异常的堆栈跟踪建议

at System.IO.Ports.SerialStream.set_RtsEnable(Boolean value)
at System.IO.Ports.SerialStream..ctor(String portName, Int32 baudRate, Parity parity, Int32 dataBits, StopBits stopBits, Int32 readTimeout, Int32 writeTimeout, Handshake handshake, Boolean dtrEnable, Boolean rtsEnable, Boolean discardNull, Byte parityReplace)
at System.IO.Ports.SerialPort.Open()