เชื่อมต่อเครื่องวัดเสียงผ่าน Serail Port ค่าเข้า แต่อ่านค่าไม่ได้ มีวิธีแก้ไขไหมครับ
Code (VB.NET)
Imports System.Data
Imports System.Data.SqlClient
Imports VB = Microsoft.VisualBasic
Imports System.IO.Ports
Imports System.Threading
Imports System.ComponentModel
Imports System
Public Class Form2
Delegate Sub SetTextCallback(ByVal [text] As String)
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
End Sub
Private Sub btnConnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConnect.Click
SerialPort1.PortName = "COM3"
SerialPort1.BaudRate = "115200"
SerialPort1.Parity = IO.Ports.Parity.None
SerialPort1.StopBits = IO.Ports.StopBits.One
SerialPort1.DataBits = 8
SerialPort1.Open()
End Sub
Private Sub btnDisconnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisconnect.Click
SerialPort1.Close()
End Sub
Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
ReceivedText(SerialPort1.ReadExisting())
End Sub
Private Sub ReceivedText(ByVal [text] As String)
If Me.txtSN.InvokeRequired Then
Dim x As New SetTextCallback(AddressOf ReceivedText)
Me.Invoke(x, New Object() {(text)})
Else
Me.txtSN.Text &= [text]
End If
End Sub
End Class
Function ReceiveSerialData() As String
' Receive strings from a serial port.
Dim returnStr As String = ""
Dim com As IO.Ports.SerialPort = Nothing
Try
com1 = My.Computer.Ports.OpenSerialPort("COM3")
com1.ReadTimeout = 10000
Do
Dim Incoming As String = com1.ReadLine()
If Incoming Is Nothing Then
Exit Do
Else
returnStr &= Incoming & vbCrLf
End If
Loop
Catch ex As TimeoutException
returnStr = "Error: Serial Port read timed out."
Finally
If com1 IsNot Nothing Then com1.Close()
End Try
Return returnStr
End Function
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