我用VB编了一个与6RA70通信通信的小程序

Private Sub Command1_Click()

Timer1.Enabled = True

End Sub

Private Sub Timer1_Timer()

Dim outdata(14) As Long

Dim j%

outdata(0) = &H2

outdata(1) = &HC

outdata(2) = &H0

outdata(3) = &H0

outdata(4) = &H0

outdata(5) = &H0

outdata(6) = &H0

outdata(7) = &H0

outdata(8) = &H0

outdata(9) = &H0

outdata(10) = &H0

outdata(11) = &H20

outdata(12) = &H7F

Dim a As Long

For j = 0 To 12

outdata(13) = outdata(13) Xor outdata(j)

Next j

txt2.Text = outdata(13)

j = 0

buf = ""

For j = 0 To 13

buf = buf & Chr(outdata(j))

Next j

If MSComm1.PortOpen = False Then

MSComm1.PortOpen = True

End If

MSComm1.Output = buf

End Sub

Private Sub MSComm1_OnComm()

Dim I%, inByte() As Byte

Dim buff$

Dim buff1$

Dim inputdata(14) As String

buff = ""

inByte = MSComm1.Input

For I = LBound(inByte) To UBound(inByte)

buff = Hex(inByte(I))

buff1 = buff1 & Hex(inByte(I)) & Chr(32)

inputdata(I) = buff

Next

If buff1 = "" Then

MsgBox "没有任何消息返回！"

Else

txt1.Text = buff1

txt3.Text = inputdata(12)

End If

End Sub



outdata(11)和outdata(12)是PZD２给定的值高位在前低位在后，outdata(1１)outdata(12)值不管哪一个一旦超过&H7F,通信就失败，但是BCC的校验是正确的，请哪位高人指点指点