串口通讯很慢 [英] Serial port communication very slow

问题描述

Public Shared Function ReceiveData() As String
            Dim RXCnt As Integer = 0
            Dim RXByte As Byte = 0
            Dim reply As String = String.Empty
            Dim STX As Byte() = {&H2, &HD}
            Dim hexwrite As String = String.Empty
            Dim ack As Double = 0
            Dim errorCode As String = Nothing
            Dim strText As String = Nothing
            Dim RXArray As Char() = New Char(2047) {}
            Dim errorDescription = String.Empty

            Dim LookUpTable As String = "0123456789ABCDEF"

            Do
                '----- Start of communication protocol handling ---------------------------------------------

                RXCnt = 0
                Do
                    RXByte = COMPort.ReadByte

                    RXArray(RXCnt) = LookUpTable(RXByte >> 4) ' Convert each byte to two hexadecimal characters

                    RXCnt = RXCnt + 1
                    RXArray(RXCnt) = LookUpTable(RXByte And 15)
                    RXCnt = RXCnt + 1

                Loop While Not ((COMPort.BytesToRead = 0))

                '----- End of communication protocol handling -------------------------------------------------------------

                recievesend = False

                reply = RXArray(0).ToString & RXArray(1).ToString

                If reply = "06" Then
                    If readwrite = True Then

                        Try
                            COMPort.Write(STX, 0, STX.Length)
                        Catch ex As TimeoutException
                            errorCodeText = String.Concat(errorCodeText, ex.Message)
                        Catch ex As InvalidOperationException
                            errorCodeText = String.Concat(errorCodeText, ex.Message)
                        Catch ex As UnauthorizedAccessException
                            errorCodeText = String.Concat(errorCodeText, ex.Message)
                        End Try

                        recievesend = True
                        hexwrite = "020D"
                    ElseIf readwrite = False Then
                        If ack < 1 Then
                            ack = ack + 1

                            Try
                                COMPort.Write(writebytes, 0, writebytes.Length)
                            Catch ex As TimeoutException
                                errorCodeText = String.Concat(errorCodeText, ex.Message)
                            Catch ex As InvalidOperationException
                                errorCodeText = String.Concat(errorCodeText, ex.Message)
                            Catch ex As UnauthorizedAccessException
                                errorCodeText = String.Concat(errorCodeText, ex.Message)
                            End Try

                            recievesend = True
                            hexstring = StringToHex(writedata)
                        Else
                            ack = 0
                        End If
                    End If
                ElseIf reply = "15" Then
                    errorCode = RXArray(3).ToString()
                End If
                Thread.Sleep(300) 'sleep between incoming bytes
            Loop While Not ((COMPort.BytesToRead = 0))

		strText = New String(RXArray, 0, RXCnt) & vbCrLf

            Return DecodeHexString(strText)

        End Function

我尝试过：



我用来从端口读取数据的代码非常慢，请帮助我，如果有任何新选项可以尝试加固读数。

What I have tried:

This code i am using to read data from the port is very slow, please help me if there are any new options to try to fasten the reading.

推荐答案

可能没有：串行端口以固定速度运行（称为波特率），它控制在连接的设备之间传输字符的最大速度它。如果串口设置为9600波特，则每秒最多可传输960个字符（大约），不能再传输。

Probably, there aren't : serial ports run at a fixed speed (known as a Baud Rate) which controls the maximum speed at which characters can be transfered between devices connected to it. If you serial port is set to 9600 baud, then you can transfer up to 960 characters per second (approximately) and no more.

引用：

我用来从端口读取数据的代码非常慢

This code i am using to read data from the port is very slow

按设计，串口通信速度非常慢。

实际串口，最大速度是115200波特，这意味着如果有一个连续的流量，则11520个标准杆秒。



你的波特实际速度是多少，每秒多少个字符。你收到了吗？

By design, Serial port communications are very slow.
On real serial port, maximum speed is 115200 bauds, which means 11520 chars par second if there is a continuous flow.

What is your actual speed in baud and how many char per seconds do you receive ?

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