How can I receive data from a PBX machine after I get gonnected to it?

Question

Hello there I'm encountering an issue recently and been searching more than two months but haven't found a solution for it yet. I have to write a program/application (which I already started in VB.NET 2010) that connects through Panasonic KX-TEM824 PBX machine via RS232 port (cable already connected : COM15/16 depending on USB I connect) and while it's connected to parse(receive) the data from the PBX itself, data that has caller ID, time of call started and ended, duration of the call and etc. I have found some already application on the Internet that does the work but they are free to try after awhile requires to buy or restart the app again. But I assume there's not much to implement on the code side. Please I really need help. I'm posting code below. P.s. it's for study purpose.

Imports System 
Imports System.ComponentModel 
Imports System.Threading 
Imports System.IO.Ports 
Public Class frmMain 
Dim myPort As Array 'COM Ports detected on the system will be stored here 
Delegate Sub SetTextCallback(ByVal [text] As String) 'Added to prevent threading errors during receiveing of data 

Private Sub frmMain_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load 
'When our form loads, auto detect all serial ports in the system and populate the cmbPort Combo box. 
myPort = IO.Ports.SerialPort.GetPortNames() 'Get all com ports available 
cmbBaud.Items.Add(9600) 'Populate the cmbBaud Combo box to common baud rates used 
cmbBaud.Items.Add(19200) 
cmbBaud.Items.Add(38400) 
cmbBaud.Items.Add(57600) 
cmbBaud.Items.Add(115200) 

For i = 0 To UBound(myPort) 
cmbPort.Items.Add(myPort(i)) 
Next 
cmbPort.Text = cmbPort.Items.Item(0) 'Set cmbPort text to the first COM port detected 
cmbBaud.Text = cmbBaud.Items.Item(0) 'Set cmbBaud text to the first Baud rate on the list 

btnDisconnect.Enabled = False 'Initially Disconnect Button is Disabled 

End Sub 

Private Sub btnConnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConnect.Click 
SerialPort1.PortName = cmbPort.Text 'Set SerialPort1 to the selected COM port at startup 
SerialPort1.BaudRate = cmbBaud.Text 'Set Baud rate to the selected value on 

'Other Serial Port Property 
SerialPort1.Parity = IO.Ports.Parity.None 
SerialPort1.StopBits = IO.Ports.StopBits.One 
SerialPort1.DataBits = 8 'Open our serial port 
SerialPort1.Open() 

btnConnect.Enabled = False 'Disable Connect button 
btnDisconnect.Enabled = True 'and Enable Disconnect button 

End Sub 

Private Sub btnDisconnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisconnect.Click 
SerialPort1.Close() 'Close our Serial Port 

btnConnect.Enabled = True 
btnDisconnect.Enabled = False 
End Sub 

Private Sub btnSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSend.Click 
SerialPort1.Write(txtTransmit.Text & vbCr) 'The text contained in the txtText will be sent to the serial port as ascii 
'plus the carriage return (Enter Key) the carriage return can be ommitted if the other end does not need it 
End Sub 

Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived 
ReceivedText(SerialPort1.ReadExisting()) 'Automatically called every time a data is received at the serialPort 
End Sub 
Private Sub ReceivedText(ByVal [text] As String) 
'compares the ID of the creating Thread to the ID of the calling Thread 
If Me.rtbReceived.InvokeRequired Then 
Dim x As New SetTextCallback(AddressOf ReceivedText) 
Me.Invoke(x, New Object() {(text)}) 
Else 
Me.rtbReceived.Text &= [text] 
End If 
End Sub 

Private Sub cmbPort_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmbPort.SelectedIndexChanged 
If SerialPort1.IsOpen = False Then 
SerialPort1.PortName = cmbPort.Text 'pop a message box to user if he is changing ports 
Else 'without disconnecting first. 
MsgBox("Valid only if port is Closed", vbCritical) 
End If 
End Sub 

Private Sub cmbBaud_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmbBaud.SelectedIndexChanged 
If SerialPort1.IsOpen = False Then 
SerialPort1.BaudRate = cmbBaud.Text 'pop a message box to user if he is changing baud rate 
Else 'without disconnecting first. 
MsgBox("Valid only if port is Closed", vbCritical) 
End If 
End Sub 
End Class

Answer 1

I also have this PBX unit, so im curious now, but I cant check it out till im back at work tomorrow.

This code looks like a msdn sample code, and has not been customised in any way for the pbx applicatiom. Perhaps you should do as hans suggested and get it working with a terminal program first, then set up your app with only the correct baud, parity and stop bits. IIRC the panasonic uses fixed settings, therefore providing options will just complicate the issue.