vbcom1.txt

VB 的COM程序

Private Sub Form_Load() '先对串口初始化
MSComm1.InBufferSize = 40
MSComm1.Settings = "9600,N,8,1"
MSComm1.InputMode = comInputModeBinary
MSComm1.NullDiscard = False
MSComm1.DTREnable = False
MSComm1.EOFEnable = False
MSComm1.RTSEnable = False
MSComm1.OutBufferCount = 0
MSComm1.InBufferCount = 0
MSComm1.InputLen = 0
MSComm1.SThreshold = 0
MSComm1.RThreshold = 1
    MSComm1.PortOpen = True
    
End Sub
Private Sub Command1_Click() '发送数据
If MSComm1.PortOpen = False Then
i = MsgBox("U must select the serial port first!", vbOKOnly, "Warning!")
Exit Sub
End If
If Text1.Text = "" Then
X = MsgBox("the  could not be """"!", vbOKOnly, "Warning!")
Text1.SetFocus
Exit Sub
End If

MSComm1.Output = Text1.Text + Chr$(13) '将数据送到数据缓存区发送
If MSComm1.OutBufferCount = 0 Then
Text2.Text = Text2.Text + "Date is enter!" + vbCr + vbLf
End If

Text3.Text = ""
Text4.Text = ""
End Sub

Private Sub MSComm1_OnComm() '利用oncomm事件接收数据
Select Case MSComm1.CommEvent
Case comEvReceive
Var = MSComm1.Input
Dim s As String
Dim tmp As String

For i = LBound(Var) To UBound(Var)

      
        If Var(i) <= 128 Then
        s = Chr(Var(i))
           
        Else
        tmp = 256# * Var(i) + Var(i + 1)
            s = Chr(tmp)
            i = i + 1

Text4.Text = Text4.Text + s
Next i

Text3.Text = Text3.Text + "The Date is received!" + vbCr + vbLf
End Select
End Sub