串口与wincc通讯

我要做用wincc读取一个智能仪表的读数，智能仪表支持R232串口通讯，日本的仪表，厂家没有相关的读取读数的程序，需要我自己写一个。哪个老师有相关wincc与串口通讯的案例，给我发一个具体的代码（网上找到的都是不完整的代码），让我参考一下，谢谢了！

问题补充：
objMSComm1.Settings = "9600,N,8,1"

最佳答案

需要知道仪表的通讯端口设置参数，在WINCC里要编写VBA脚本程序。
这里有一段程序，你可以参考下：高精度电压表(24bit)  
Public Sub ComPortOpen() ”开串口
    With MSComm1
        .CommPort = PortValue              ”使用COM1
        .Settings = "9600,N,8,1"       ”设置通信口参数
        .InBufferSize = 40
        ”设置MSComm1接收缓冲区为40字节
        ”.OutBufferSize = 2
        ”设置MSComm1发送缓冲区为2字节
        .InputMode = comInputModeBinary
        ”设置接收数据模式为二进制形式
        .InputLen = 1
        ”设置Input 一次从接收缓冲读取字节数为1
        ”.SThreshold = 1
        ”设置Output 一次从发送缓冲读取字节数为1
        .InBufferCount = 0  ”清除接收缓冲区
        ”.OutBufferCount = 0     ”清除发送缓冲区
        ”MaxW = -99
        ”最大值赋初值
        ”MinW = 99             ”最小值赋初值
        ”w = 0
        ”数据个数计数器清零
        .RThreshold = 1
        On Error Resume Next
        ”设置接收一个字节产生OnComm事件
        If .PortOpen = False Then
            ”判断通信口是否打开
            .PortOpen = True       ”打开通信口
            If Err Then        ”错误处理
                msg = MsgBox(" 串口 COM" & PortValue & " 无效！ ", vbOKOnly, "警告")
                Exit Sub
            End If
        End If
    End With
    ”MsgBox "端口已打开"
End Sub
Public Sub ComPortClose() ”关串口
    MSComm1.PortOpen = False
    ”   MsgBox "端口已关闭"
End Sub
Private Sub MSComm1_OnComm()
    Call recive
End Sub
Private Sub Option1_Click(Index As Integer)
    If MSComm1.PortOpen = True Then
        Call ComPortClose
    End If
    PortValue = Index + 1
    Call ComPortOpen
End Sub
Private Sub recive() ”检测起始位并接收数据
    Dim Buffer As Variant
    Dim Arr() As Byte
    Dim inData(5) As Byte
    Dim count  As Integer
    Dim temp As Byte    
”  MsgBox "OnComm"
    With MSComm1
       Select Case .CommEvent
            ”判断MSComm1通信事件
                Case comEvReceive
                    ”收到Rthreshold个字节产生的接收事件
                    Buffer = .Input
                    Arr = Buffer
                   
                    ”读取一个接收字节
                    ” Text1.Text = Arr(0)
                    If Arr(0) = &H1B Then
                        .RThreshold = 0
                        Do
                            DoEvents
                        Loop Until .InBufferCount >= 4
                       
                        For i = 1 To 4
                            ”count = .InBufferCount
                            Buffer = .Input
                            Arr = Buffer
                            inData(i) = Arr(0)
                        Next i
                        If inData(4) = &HA Then
                            If (inData(1) Mod 64) >= 32 Then
                                .RThreshold = 1
                                Exit Sub
                            End If
                            valueFlag = 1
                            ”0.000003814697265625
                            temp = inData(1) Mod 16
                            If temp <= 7 Then
                                value = inData(1) Mod 8
                                value = value * 256 * 256
                                value = value + Val(inData(2)) * 256
                                value = value + Val(inData(3))
                                value = value * 3.814697265625E-06
                                ”Text1.Text = Format(value, "0.000,000")
                            Else
                                value = inData(1) Mod 8
                                value = value * 256 * 256
                                value = value + Val(inData(2)) * 256
                                value = value + Val(inData(3))
                                value = value * 3.814697265625E-06
                                value = 0 – value
                            End If
                            temp = inData(1) Mod 128
                            ” test OF
                            If temp >= 64 Then
                                If value < 0 Then
                                    value = value – 0.000004
                                Else
                                    value = value + 0.000004
                                End If
                            End If
                            ”检测自动刷新
                            If Check1.value Then
                                 ”valueFlag = 1
                                 Call display
                            End If
                        Else
                            .RThreshold = 1
                            Exit Sub
                        End If
                        .InBufferCount = 0
                        .RThreshold = 1
                    End If
            Case Else
        End Select
    End With
    ”Text1.Text = Text1.Text + 1
End Sub
Private Sub Option2_Click(Index As Integer)
    func = Index + 1
End Sub
Public Sub display() ”判断功能并显示
   
    ”功能选择
    Select Case func
        Case 1 ”当前值
            value2 = value
           
        Case 2 ”平均值
            If numCount > 100000 Then
                numCount = 1
                valueSum = 0
            End If
            If valueFlag = 1 Then
                valueSum = valueSum + value
                value2 = valueSum / numCount
                numCount = numCount + 1
                valueFlag = 0
                Label6.Caption = Str(numCount – 1)
            End If
        Case 3 ”最大值
            If value > value2 Then
                value2 = value
            End If
        Case 4 ”最小值
            If value < value2 Then
                value2 = value
            End If
        Case Else
    End Select
    ”Text1.Text = Str(valueSum)
    Label1.Caption = Format(value2, "0.000,000")
End Sub

提问者对于答案的评价：
谢谢了，参考一下