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一个简单的VB串口发送程序（源码）
'-----发送按钮Click事件子程序-----------
Private Sub Fasong_Click()
Dim JIHAO(0) As Byte ’机号
Dim head_data(4) As Byte ’5 Byte控制字
Dim end_data(0) As Byte '1 Byte 结束字
JIHAO(0) = Val(Text3.Text)
head_data(0) = Val(Text4.Text)
head_data(2) = &HEE 'TIMH
head_data(3) = &HEE 'TIML
head_data(4) = Val(Combo1.Text) 'INMOD
end_data(0) = &HFF
If Combo2.Text = "增加" Then head_data(1) = &H99
If Combo2.Text = "清空" Then head_data(1) = &H33
If Combo2.Text = "删除" Then head_data(1) = &H32
Ready = 0: ErrCount = 0
On Error GoTo ERRORCOM ’打开错误处理
'----------------------------------------------------------
If com1.value Then MSComm1.CommPort = 1 'Use com1
If com2.value Then MSComm1.CommPort = 2 'Use com2
MSComm1.Settings = FORM1.Combo3.Text + ",M,8,2" '设定波特率和置校验和位为1
MSComm1.InputLen = 0 '
MSComm1.PortOpen = -1 'Open the port
MSComm1.OutBufferCount = 0
MSComm1.Output = JIHAO ‘发送机号
MSComm1.PortOpen = False ’关闭串口
MSComm1.Settings = FORM1.Combo3.Text + ",S,8,2" '设定波特率和置校验和位为空
MSComm1.OutBufferCount = 0
MSComm1.PortOpen = True
MSComm1.Output = head_data
MSComm1.Output = Text2.Text
MSComm1.Output = end_data
MSComm1.PortOpen = False
Text1.Text = "发送成功!" + Chr(13) & Chr(10) + "发送至" + Text3.Text + "屏体," + "信息编号:" + Text4.Text + Chr(13) & Chr(10) + Chr(13) & Chr(10) + Text1.Text
GoTo comend
ERRORCOM:
Text1.Text = "ERROR!请重新选择COM口!" + Chr(13) & Chr(10) + Chr(13) & Chr(10) + Text1.Text
comend:
On Error GoTo 0
End Sub
