VB串口通信(附图教程

1、界面如下：代码如下：Private Sub Form_Load()If MSComm1.PortOpen = True Then MSComm1.PortOpen = FalseElseEnd IfCombo1.AddItem COM1Combo1.AddItem COM2Combo1.AddItem COM3Combo1.AddItem COM4Combo1.AddItem COM5Combo1.AddItem COM6Combo1.AddItem COM7Combo1.AddItem COM8Combo1.AddItem COM9Combo1.AddItem COM10Combo1.Add

2、Item COM11Combo1.AddItem COM12Combo1.AddItem COM13Combo1.AddItem COM14Combo1.AddItem COM15Combo1.AddItem COM16Combo1.ListIndex = 2Combo2.AddItem Combo2.AddItem Combo2.AddItem Combo2.AddItem 57600Combo2.AddItem 38400Combo2.AddItem 28800Combo2.AddItem 19200Combo2.AddItem 14400Combo2.AddItem 12800Combo

3、2.AddItem 11520Combo2.AddItem 9600Combo2.AddItem 4800Combo2.AddItem 2400Combo2.AddItem 1200Combo2.AddItem 600Combo3.AddItem 无NoneCombo3.AddItem 奇OddCombo3.AddItem 偶EvenCombo4.AddItem 4Combo4.AddItem 5Combo4.AddItem 6Combo4.AddItem 7Combo4.AddItem 8Combo5.AddItem 1Combo5.AddItem 2MSComm1.CommPort = C

4、ombo1.ListIndex + 1MSComm1.Settings = 9600,n,8,1ComOpen.Caption = 打开串口Shape1.FillColor = &HFFFFC0End SubPrivate Sub ComOpen_Click()On Error GoTo uerror 发现错误跳转到错误处理If ComOpen.Caption = 关闭串口 Then MSComm1.PortOpen = False ComOpen.Caption = 打开串口 按钮文字改变 Shape1.FillColor = &HFFFFC0 灯颜色改变Else MSComm1.PortO

5、pen = True ComOpen.Caption = 关闭串口 Shape1.FillColor = &HFFEnd IfExit Subuerror: msg$ = 无效端口号 错误显示 Title$ = 串口调试助手 X = MsgBox(msg$, 48, Title$) 48标示显示警告图标End SubPrivate Sub MSComm1_OnComm() Dim BytReceived() As Byte Dim strBuff As String Dim i As Integer Select Case MSComm1.CommEvent 事件发生 Case 2 Cls M

6、SComm1.InputLen = 0 读入缓冲区全部内容 strBuff = MSComm1.Input 读入到缓冲区 Label10.Caption = Label10.Caption + Len(strBuff) 接收计数 If MSComm1.InputMode = comInputModeBinary Then BytReceived() = strBuff 如果是二进制接收模式则进行数据处理，否则直接显示字符串 For i = 0 To UBound(BytReceived) If Len(Hex(BytReceived(i) = 1 Then strData = strData

7、& 0 & Hex(BytReceived(i) & 如果只有一个字符，则前补0，如F显示0F，最后补空格 Else 方便显示观察如： 00 0F FE strData = strData & Hex(BytReceived(i) & End If Next TextReceive = TextReceive & strData strData = Else TextReceive = TextReceive & strBuff End If End SelectEnd SubPrivate Sub ComSend1_Click() 手动发送Dim Temp(0) As ByteDim str

8、Buff As StringIf Option1.Value = True Then 如果显示16进制发送则进行16进制处理 ，这里只发送一个 Temp(0) = &H & TextSend MSComm1.Output = Temp 发送一个16进制Else strBuff = TextSendEnd IfIf MSComm1.PortOpen = False Then MsgBox 请打开串口End IfOn Error GoTo uerrorMSComm1.Output = strBuffLabel11.Caption = Label11.Caption + Len(strBuff) 发

9、送计数uerror:End SubPrivate Sub ComSend2_Click()If ComSend2.Caption = 自动发送 Then ComSend2.Caption = 关闭自动发送 Timer1.Interval = TextTime.Text Timer1.Enabled = TrueElse ComSend2.Caption = 自动发送 Timer1.Enabled = FalseEnd IfEnd SubPrivate Sub ComClean1_Click()TextSend.Text = 清空发送窗口End SubPrivate Sub Option3_Cl

10、ick()MSComm1.InputMode = comInputModeBinary 选择接收方式End SubPrivate Sub Option4_Click()MSComm1.InputMode = comInputModeText 选择接收方式End SubPrivate Sub Timer1_Timer()Call ComSend1_Click 定时调用手动发送End SubPrivate Sub Timer2_Timer()If Combo3 = 无None Then MSComm1.Settings = Str(Combo2) + N + Str(Combo4) + Str(C

11、ombo5)ElseIf Combo3 = 奇Odd Then MSComm1.Settings = Str(Combo2) + O + Str(Combo4) + Str(Combo5)ElseIf Combo3 = 偶Even Then MSComm1.Settings = Str(Combo2) + E + Str(Combo4) + Str(Combo5)End IfEnd SubPrivate Sub Combo1_Click()If MSComm1.PortOpen = True Then 如果串口打开先关闭后再进行其他操作 MSComm1.PortOpen = FalseEnd

12、IfMSComm1.CommPort = Combo1.ListIndex + 1 读取com口号End SubPrivate Sub ComClean3_Click()Label10.Caption = 0Label11.Caption = 0End SubPrivate Sub ComClean2_Click()TextReceive.Text = 接收窗口End Sub功能上：实现了字符串的发送和接收，8位数据的十六进制发送和接收，有端口，波特率等设置。缺点：1：只可以发送两位十六进制数。2：接收和发送的显示数据上有点不同步，十六进制的没有算进去。3：没有TXT的文件发送和接收的功能。如

13、需要源程序的，可下载本文的图片，下载后把图片的.jpg格式改为.rar格式就可以解压出来了。附：MSComm控件的属性：属性说明(Name)MSComm控件的名称(自定义)打开属性页CommPort获得或设置通讯端口号DTREnable决定在通讯过程中是否使数据终端机状态线有效。取值为：TrueFalseEOFEnable获得或设置是否搜索EOF字符。取值为：TrueFalseHandshaking获得或设置软件的握手协议。取值为：0 comNone1 comXOnXoff2 comRTS3 comRTSXOnXOffInBufferSize获得或设置接收缓冲区的大小，以字节数为单位。Index在对象数组中的编号InputLen获得或设置输入属性从接收缓冲区读出的字符数。InputMode获得或设置输入属性检索的数据类型。取值为：0 comInputModeText1 comInputModeBinaryLeft距离容器左边框的距离NullDiscard决定是否将空字符串从端口传送到接收缓冲区。取值为：TrueFalse