VB上位机温度采集(含源程序代码).doc

VB程序 Option Explicit Dim NowX As Integer Dim MaxPlotNo As Long Dim PreValue As Single Private Sub cmbCOM_Click() If cmbCOM.ListIndex + 1 = MSComm1.CommPort Then Exit Sub Timer1.Enabled = False TimeDelay 100 If MSComm1.PortOpen Then MSComm1.PortOpen = False End If lblMsg.Caption = 已停止检测并关闭通讯端口 cmdOpenCOM.Enabled = True End Sub Private Sub cmdEnd_Click() End End Sub Private Sub cmdOpenCOM_Click() If cmbCOM.ListIndex = 0 And cmbCOM.ListIndex = 16 Then MSComm1.CommPort = cmbCOM.ListIndex + 1 Else MsgBox 指定通信端口时发生错误！, vbCritical + vbOKOnly, 系统信息 Exit Sub End If On Error GoTo comErr MSComm1.Settings = 9600,n,8,1 MSComm1.PortOpen = True cmdOpenCOM.Enabled = False cmdStart.Enabled = True lblMsg.Caption = 可单击【开始检测】按钮，执行检测的工作。 Exit Sub comErr: MsgBox 打开通信端口时发生错误！请确定通信端口存在且正常。, vbCritical + vbOKOnly, 系统信息 End Sub Private Sub cmdStart_Click() Timer1.Enabled = Not Timer1.Enabled If Timer1.Enabled Then cmdStart.Caption = 停止检测 Else cmdStart.Caption = 开始检测 lblMsg.Caption = 已停止检测 End If End Sub Private Sub Form_Load() Dim i% MaxPlotNo = 100 cmbCOM.Clear cmbCOM.AddItem COM1 cmbCOM.AddItem COM2 cmbCOM.AddItem COM3(USB) cmbCOM.AddItem COM4(USB) cmbCOM.AddItem COM5 cmbCOM.AddItem COM6 cmbCOM.AddItem COM7 cmbCOM.AddItem COM8 cmbCOM.AddItem COM9 cmbCOM.AddItem COM10 cmbCOM.AddItem COM11 cmbCOM.AddItem COM12 cmbCOM.AddItem COM12 cmbCOM.AddItem COM14 cmbCOM.AddItem COM15 cmbCOM.AddItem COM16 cmbCOM.ListIndex = 0 cmdStart.Enabled = False 以下设定绘图范围，(Xmin,YMax)-(XMax,YMin) picVoltage.Scale (0, 50)-(MaxPlotNo, 0) picVoltage.DrawWidth = 2 使用两个像素宽度的画笔 End Sub Private Sub Label2_Click() End Sub Private Sub lblValue_Click() End Sub Private Sub MSComm1_OnComm() End Sub Private Sub Timer1_Timer() Dim Buf$, ValueStr As Single, Pos1% Buf$ = Buf$ + MSComm1.Input TimeDelay 2150 ValueStr = Val(Mid(Buf,