代码之家 › 专栏 › 技术社区 › Mawg says reinstate Monica

为什么这个vb6代码不能打开串口?

vb6

Mawg says reinstate Monica · 技术社区 · 14 年前

Dim MSComm1 As MSComm

on error goto cant_open_com1

MSComm1.CommPort = 1
MSComm1.Settings = "9600,N,8,1"
MSComm1.DTREnable = True
MSComm1.Handshaking = comRTS
MSComm1.InBufferSize = 12 + 1  ' +1 for the CR
MSComm1.RThreshold = MSComm1.InBufferSize
MSComm1.RTSEnable = True
MSComm1.InputLen = 0 ' read entire input buffer
MSComm1.InputMode = comInputModeText
MSComm1.NullDiscard = True
MSComm1.OutBufferSize = 0 ' not used, we don't write to the serial port
MSComm1.SThreshold = MSComm1.OutBufferSize
'MSComm1.ParityReplace = ?

MSComm1.PortOpen = True

控制传递给错误处理程序

2 回复 | 直到 14 年前

raven 14 年前

当您说“控制传递给错误处理程序”时,您是否忘记添加 Exit Sub ? 在你的评论中,你说你添加了新的声明,但是你仍然有问题吗?嗯,我刚刚运行了这个代码,打开端口没有问题。

Private Sub Form_Load()

  Dim MSComm1 As New MSComm

  On Error GoTo cant_open_com1

  MSComm1.CommPort = 1
  MSComm1.Settings = "9600,N,8,1"
  MSComm1.DTREnable = True
  MSComm1.Handshaking = comRTS
  MSComm1.InBufferSize = 12 + 1
  MSComm1.RThreshold = MSComm1.InBufferSize
  MSComm1.RTSEnable = True
  MSComm1.InputLen = 0
  MSComm1.InputMode = comInputModeText
  MSComm1.NullDiscard = True
  MSComm1.OutBufferSize = 0
  MSComm1.SThreshold = MSComm1.OutBufferSize

  MSComm1.PortOpen = True

  Exit Sub

cant_open_com1:
    Debug.Print Err.Description

End Sub