Question

我有编程手册协议，但是当我编写代码时，vb.net会返回错误信息。

以下是字节数组的表结构

职位1 2 3 4 5 6 7 8

名称SOH LEN SEQ CMD DATA Post-amble BCC ETX

Lenth / bytes 1 1 1 1 0-200 1 4 1

值（01h）（20h-FFh）（20h-FFh）（20h-FFh）（20h-FFh）（05h）（30h-3Fh）（03h）

缩写：

“SOH” - （标题开头）打包邮件

“LEN” - 从位置2到位置6的总字节数加上固定偏移量20h。

“SEQ” - 数据包的序列号。 SLAVE在回复消息中放置相同的“SEQ”。在SLAVE的情况下收到与上次正确接收的消息相同的“SEQ”和“CMD”的消息，设备忽略消息并重复发送到主机的最后一个数据包。

“CMD” - 命令代码

“DATA” - 数据，根据命令。如果没有数据，则长度字段为零。

“BCC” - 控制总和（0000h-FFFFh）。从位置2到位置6的数据字节总和。控制和是以ASCІІ类型转移（12А被转移为31h32h3Аh3Вh）。

“ETX” - （TeXt结束）打包邮件结束。

代码示例：

Public Class Form1

Private WithEvents sp As System.IO.Ports.SerialPort

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    For Each y As String In System.IO.Ports.SerialPort.GetPortNames
        Me.ComboBox1.Items.Add(y)
    Next
    sp = New IO.Ports.SerialPort("COM4")
    sp.StopBits = IO.Ports.StopBits.One
    sp.BaudRate = 9600
    sp.DataBits = 8
    sp.Parity = IO.Ports.Parity.None
    sp.Handshake = IO.Ports.Handshake.None

    sp.Open()
    Dim by As Byte = &H20

    ' MsgBox(&H20)
End Sub

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    Try
        Dim By(9) As Byte
        By(0) = 1
        By(1) = &H2 + &H20
        By(2) = &H58
        By(3) = &H45
        By(4) = &H5
        Dim S As String = Hex(&H58 Xor &H45)
        '  MsgBox(S)
        By(5) = &H30
        By(6) = &H30
        By(7) = &H31
        By(8) = &H3D
        By(9) = &H3

        sp.Write(By, 0, By.Length - 1)
       ' MsgBox(sp.ReadByte)
    Catch ex As Exception
        MsgBox(ex.Message)
    End Try
End Sub

Private Sub sp_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles sp.DataReceived
    Dim rec As System.IO.Ports.SerialPort = sender
    MsgBox(Hex(rec.ReadByte))
End Sub

结束班

Answer 1

Annael你可能会这样做，通过调用更新函数并给出500毫秒的延迟将有所作为。现在，在接收数据时，您可以接收输入数据

Dim inputData As String = ""// Declare this as a global variable in the program
    Private WithEvents sp As System.IO.Ports.SerialPort

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
   For Each y As String In System.IO.Ports.SerialPort.GetPortNames
            Me.ComboBox1.Items.Add(y)//the code you have written to add Serial ports

SerialPort1.PortName = ComboBox1.Text//this will access your com port as your button
        Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim by As Byte = &H20    
                By(0) = 1
                By(1) = &H2 + &H20
                By(2) = &H58
                By(3) = &H45
                By(4) = &H5
                Dim S As String = Hex(&H58 Xor &H45)
                '  MsgBox(S)
                By(5) = &H30
                By(6) = &H30
                By(7) = &H31
                By(8) = &H3D
                By(9) = &H3
            SerialPort1.BaudRate = 115200
            SerialPort1.Open()
            SerialPort1.Write(By)
        Private Sub SerialPort1_DataReceived(sender As System.Object, e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived

            Threading.Thread.Sleep(500) ' 500ms delay induced to receive the email
            inputData = SerialPort1.ReadExisting 'or SerialPort1.ReadLine


            Me.Invoke(New EventHandler(AddressOf DoUpdate))

    Public Sub DoUpdate()

                MsgBox(inputData)

串行端口使用Packed消息在VB.NET中发送数据

1 个答案: