現(xiàn)象：現(xiàn)做個(gè)一個(gè)軟件實(shí)現(xiàn)和FX-PLC通訊。畫面功能和觸摸屏差不多，按鈕，讀寫數(shù)據(jù)都好用。但是有個(gè)毛病，我想實(shí)時(shí)讀PLC 的D中數(shù)據(jù)，可是我一點(diǎn)畫面按鈕后，讀D中的數(shù)據(jù)就不動(dòng)了。請(qǐng)問(wèn)怎么解決。不論我按什么鍵，它都一直讀D中的數(shù)據(jù)，不停。

是VB寫的軟件和PLC通訊嗎

是

你把VB程序發(fā)出來(lái)

Private Sub Timer3_Timer()
      If MSComm1.PortOpen = True Then
      Dim outstring As String
      Dim instring As String
      Dim d As Long
      Dim e As String
      Dim f As String
      MSComm1.OutBufferCount = 0
      MSComm1.InBufferCount = 0
      outstring = Chr(&H2) + "0" + "119002" + Chr(&H3) + "60"  '讀D200數(shù)據(jù)
      MSComm1.Output = outstring
      Do
         DoEvents
         Loop Until MSComm1.InBufferCount = 8
      MSComm1.InputMode = comInputModeText
      MSComm1.InputLen = 0
      instring = MSComm1.Input
      e = instring
      f = Mid(instring, 2, 4)
      d = CLng("&H" & f)
      Text5.Text = (d And &HFF00) \ &H100 + (d And &HFF) * &H100
      End If
      If Text5.Text = "1" Then
      Label2.Caption = "非常停止中"
      End If
      If Text5.Text = "2" Then
      Label2.Caption = "暫停中"
      End If
End Sub

Loop Until MSComm1.InBufferCount = 8
是 MSComm1.InBufferCount =8條件不成立
數(shù)據(jù)沒讀進(jìn)來(lái)

讀出來(lái)了 ，只要不點(diǎn)畫面其他鍵，數(shù)據(jù)一直變化和PLC中D200同步，我聯(lián)機(jī)試了。但一點(diǎn)別的鍵就停止了。主要是怎么叫他不停��！

加一句
Timer3_Timer=FALSE

If MSComm1.PortOpen = True Then

還是那樣子哦，你那里人？

蘇州你呢

大連

吧MSComm1.InputLen = 0
去掉