为什么清除不掉缓冲区啊


Private Sub hexReceive()
 
On Error GoTo Err
    Dim ReceiveArr() As Byte                                                        ' 接收数据数组
    Dim receiveData As String                                                       ' 数据暂存
    Dim Counter As Integer                                                          ' 接收数据个数计数器
    Dim i As Integer                                                                ' 循环变量
    
    If (MSComm.InBufferCount > 0) Then
        Counter = MSComm.InBufferCount                                              ' 读取接收数据个数
       Print receiveData
        receiveData = ""                                                           ' 清缓冲
                ReceiveArr = MSComm.Input                                                   ' 数据放入数组
        
        For i = 0 To (Counter - 1) Step 1                                           ' 数据格式处理            If (ReceiveArr(i) < 16) Then
                receiveData = receiveData & "0" + Hex(ReceiveArr(i))     ' 小于16，前面加0
            Else
                receiveData = receiveData & Hex(ReceiveArr(i))            ' 加空格显示
            End If        Next i
        
    End If
  Call xianshi(Mid(receiveData, 13, 8))
  
  
  
Err:End Sub
       为什么 我第2次 接收的总会是上一次 接受到的呢?
    是 我的缓冲取 没有清除?   但是我每次 发送 的时候都清楚了的啊
Private Sub hexSend()On Error Resume Next
    Dim outputLen As Integer                                                        ' 发送数据长度
    Dim outData As String                                                           ' 发送数据暂存
    Dim SendArr() As Byte                                                           ' 发送数组
    Dim TemporarySave As String                                                     ' 数据暂存
    Dim dataCount As Integer                                                        ' 数据个数计数
    Dim i As Integer                                                                ' 局部变量
     MSComm.OutBufferCount = 0
    MSComm.InBufferCount = 0