程序b宝典bVB串口通讯实例.doc

[程序宝典]VB串口通讯实例??程序匠人??? 2005-9-22 14:23:00???? 阅读全文(3939) | 回复(0) | 引用(0) ?|? 查看《匠人的百宝箱》代理商品 VB串口通讯实例作者：liwenzhao高精度电压表(24bit)? VB源程序Dim PortValue As Integer??? 端口号选择1-4Dim value As Double???????? 当前一次取值Dim value2 As Double??????? 要显示的值Dim valueSum As Double??????? 和Dim numCount As Double????? 算平均值是的计数个数Dim func As Integer???????? 功能号标志1-4Dim valueFlag As Integer Check1_Click()为控制Command1是否Enabled Private Sub Check1_Click()自动刷新 被选中则 刷新按钮无效If Check1.value Then??? Command1.Enabled = FalseElse??? Command1.Enabled = True??? ??? Command1.SetFocusEnd IfEnd SubPrivate Sub Command1_Click()??? 显示??? Call displayEnd SubPrivate Sub Command2_Click() 复位??? valueSum = 0 清计数和??? numCount = 1 清计数个数??? Label6.Caption = Str(numCount - 1) 显示复位??? value = 0??? 当前一次取值value2 = 0??? 要显示的值valueFlag = 0??? Call displayEnd Sub Private Sub Form_Activate()??? numCount = 1??? value = 0??? valueSum = 0??? PortValue = 1??? Text1.Visible = False??? Label6.Caption = 0??? Option1(0).value = True??? Option2(0).value = True 为什么两个都是True??? Command1.SetFocus???SetFocus是什么？ Label1.Caption = Format(value2, 0.000,000)???Format为格式输出函数 For i = 0 To 3??????? If Option2(i).value = True Then??????????? func = i + 1??????? End If??? Next i??? Check1.value = 1??? Call ComPortOpenEnd Sub 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?????? ?OutBufferSize是以字符为单位的？？？ .InputMode = comInputModeBinary??????? 设置接收数据模式为二进制形式??????? .InputLen = 1?????? ?InputLen单位是字符数 设置Input 一次从接收缓冲读取字节数为1??????? .SThreshold = 1VB中SThreshold单位是字符数 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 Resu