RS485通讯的请一上

RS485通讯的求助请高手指点一下
我需要MSCOMM控件发送指令到RS485 终端会反馈一组字符但问题是指令是类似“86 01 05 0F 12”一类的而我找的代码中是byte 写出的是&HFF &HAA这样的我不知道指令如何转换为我需要的指令啊菜鸟求教高手指导一下多谢了。代码如下：
Private Sub Form_Load()
MSComm1.CommPort = 1 '利用串口COM1进行通讯
MSComm1.InputLen = 0 '每次读取接收缓冲区的1个字节
MSComm1.OutBufferSize = 512 '设置发送缓冲区为512字节
MSComm1.InBufferSize = 512 '设置接收缓冲区为2048字节
MSComm1.OutBufferCount = 0 '清除发送缓冲区
MSComm1.InBufferCount = 0 '清除接收缓冲区
MSComm1.InputMode = comInputModeBinary '数据传输设置为二进制格式
MSComm1.RThreshold = 1 '一次性接收起始码1个字节'可触发On_Comm
MSComm1.Settings = "2400,N,8,1" '设置波特率、校验位(1)、数据位、停止位
MSComm1.PortOpen = True '打开通信口COM1---需要连接RS485
Text1 = ""
End Sub

Private Sub Command1_Click()
'手动发送键
Dim DatTempBuf(30) As Byte '发送字节长31
Dim OutDatV As Variant
MSComm1.OutBufferCount = 0 '清除发送缓冲区
MSComm1.OutBufferCount = 0 '清除发送缓冲区MSComm1.OutBufferCount = 0
If MSComm1.PortOpen = False Then
MsgBox "串口未打开", 52, "提示"
Exit Sub
End If
DatTempBuf(0) = &HFF
DatTempBuf(1) = &H55
DatTempBuf(2) = &HAA
DatTempBuf(3) = &H4
DatTempBuf(4) = &H0
DatTempBuf(5) = &H3
DatTempBuf(6) = &H7
MSComm1.Output = DatTempBuf
MSComm1.InBufferCount = 0 '清除接收缓冲区
MSComm1.RThreshold = 1 '所要接收的数据长度
End Sub

Private Sub MSComm1_OnComm() '接收数据
Dim strBuff As String
Dim i As Integer
Select Case MSComm1.CommEvent
Case 2
MSComm1.InputLen = 0
strBuff = MSComm1.Input
BytReceived() = strBuff
For i = 0 To UBound(BytReceived) '接收数据处理为16进制
If Len(Hex(BytReceived(i))) = 1 Then
strData = strData & "0" & Hex(BytReceived(i))
Else
strData = strData & Hex(BytReceived(i))

End If
Next
If Len(strData) = 60 Then
Text1 = strData '数据处理--处理后进入对应的数据库
strData = ""
End If
End Select
End Sub
[最优解释]


ption Explicit
Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Dim strData As String
Private Sub Form_Load()
  MSComm1.CommPort = 1          '利用串口COM1进行通讯
  MSComm1.InputLen = 1          '每次读取接收缓冲区的1个字节
  MSComm1.OutBufferSize = 512   '设置发送缓冲区为512字节
  MSComm1.InBufferSize = 512    '设置接收缓冲区为512字节
  MSComm1.OutBufferCount = 0    '清除发送缓冲区
  MSComm1.InBufferCount = 0     '清除接收缓冲区
  MSComm1.InputMode = comInputModeBinary    '数据传输设置为二进制格式
  MSComm1.RThreshold = 1        '每接收一个字符就触发一次OnComm事件
  MSComm1.Settings = "2400,N,8,1"           '设置波特率、校验位(1)、数据位、停止位
  If Not MSComm1.PortOpen Then MSComm1.PortOpen = True        '打开通信口COM1---需要连接RS485
  Text1.Text = ""
End Sub

Private Sub Command1_Click()
    Dim DatTempBuf(0 To 2) As Byte
    Dim OutDatV As Variant
On Error GoTo errSub
    If Not MSComm1.PortOpen Then MSComm1.PortOpen = True
'    DatTempBuf(0) = &HFF
'    DatTempBuf(1) = &H55
'    DatTempBuf(2) = &HAA
'    DatTempBuf(3) = &H4
'    DatTempBuf(4) = &H0
'    DatTempBuf(5) = &H3
'    DatTempBuf(6) = &H7
    DatTempBuf(0) = &H68
    DatTempBuf(1) = &HF
    DatTempBuf(2) = &H43
    MSComm1.Output = DatTempBuf
    Exit Sub
errSub:

End Sub

Private Sub MSComm1_OnComm() '接收数据
  Dim strBuff As String
  Dim i As Integer
  Dim varInput As Variant
On Error GoTo errSub
  Select Case MSComm1.CommEvent
    Case 2
        strData = ""
        MSComm1.RThreshold = 0          '屏蔽掉OnComm事件的触发
        Sleep 20                        '等待20ms，以便数据完全上传 
 
        Do
            If Not IsNull(varInput) Then varInput = Null
            varInput = MSComm1.Input    '每次读取一个数据
            If Not IsNull(varInput) Then
                strData = strData & Right("00" & Hex("00" & varInput(0)), 2) & " "
            End If
        Loop Until MSComm1.InBufferCount = 0
        Text1.Text = strData
        MSComm1.RThreshold = 1
  End Select
  Exit Sub
errSub:

End Sub

[其他解释]
Modbus 协议是基于时间来分割数据帧的，所以VB 实现起来有问题。
[其他解释]


Option Explicit
Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long)
Dim strData As String
Private Sub Form_Load()
  MSComm1.CommPort = 1          '利用串口COM1进行通讯
  MSComm1.InputLen = 1          '每次读取接收缓冲区的1个字节
  MSComm1.OutBufferSize = 512   '设置发送缓冲区为512字节
  MSComm1.InBufferSize = 512    '设置接收缓冲区为512字节
  MSComm1.OutBufferCount = 0    '清除发送缓冲区
  MSComm1.InBufferCount = 0     '清除接收缓冲区
  MSComm1.InputMode = comInputModeBinary    '数据传输设置为二进制格式
  MSComm1.RThreshold = 1        '每接收一个字符就触发一次OnComm事件
  MSComm1.Settings = "2400,N,8,1"           '设置波特率、校验位(1)、数据位、停止位
  If Not MSComm1.PortOpen Then MSComm1.PortOpen = True        '打开通信口COM1---需要连接RS485
  Text1.Text = ""
End Sub

Private Sub Command1_Click()
    Dim DatTempBuf(0 To 6) As Byte
    Dim OutDatV As Variant
On Error GoTo errSub
    If Not MSComm1.PortOpen Then MSComm1.PortOpen = True
    DatTempBuf(0) = &HFF
    DatTempBuf(1) = &H55
    DatTempBuf(2) = &HAA
    DatTempBuf(3) = &H4
    DatTempBuf(4) = &H0
    DatTempBuf(5) = &H3
    DatTempBuf(6) = &H7
    MSComm1.Output = DatTempBuf
    Exit Sub
errSub:

End Sub

Private Sub MSComm1_OnComm() '接收数据
  Dim strBuff As String
  Dim i As Integer 
 
  Dim varInput As Variant
On Error GoTo errSub
  Select Case MSComm1.CommEvent
    Case 2
        strData = ""
        MSComm1.RThreshold = 0          '屏蔽掉OnComm事件的触发
        Sleep 20                        '等待20ms，以便数据完全上传
        Do
            If Not IsNull(varInput) Then varInput = Null
            varInput = MSComm1.Input    '每次读取一个数据
            If Not IsNull(varInput) Then
                strData = strData & Right("00" & Hex("00" & varInput(0)), 2) & " "
            End If
        Loop Until MSComm1.InBufferCount = 0
        Text1.Text = strData
        MSComm1.RThreshold = 1
  End Select
  Exit Sub
errSub:

End Sub

[其他解释]

引用:

Modbus 协议是基于时间来分割数据帧的，所以VB 实现起来有问题。

你好那有没有什么方法可以实现我设想的

利用timer控件以一定频率发送我所固定好的指令（形如：68 0F 04 44 ） 485及硬件端的反馈设计都是别人调试好的
[其他解释]
Veron_04

谢谢我先去测试下您修改的代码。
[其他解释]
DatTempBuf参数中我希望传输的是 "68 0F 43" 这样类似的指令而代码中是 &HFF &HAA 这样的我不明白怎么进行转换如果传输的指令不是指定的 "68 0F 43"这样的话 485那边的硬件是不会给反馈的。
[其他解释]
前提是你的68和43必须是16进制数据
[其他解释]
好的我明白了其实DatTempBuf赋值的时候 &H + 16进制就是一种表达多谢多谢我去修改测试下先。
[其他解释]
怎样给分啊问题解决了非常感谢
[其他解释]
.......
会发帖，不会结贴？左下有个红色按钮，赫然写着：结贴
[其他解释]
再次感谢总算会结贴给分了
[其他解释]
受教了！

RS485通讯的 请一上

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RS485通讯的请一上