Comm Starter

[New_Newton]

Hi im trying to access the com port with VB6 programming does anyone have any code to get me on my way....

[Protocol]

I've been trying to do that for the longest while without the use of 3rd party controls....

Currently I'm still looking...

Anyone with a solution?

[chris_at_work]

I have created an application that communicates with a modem connected to a com port. This uses 'Microsoft comm control 6.0' (MSCOMM32.OCX).

I have put one of these controls and a timer on a form. The application answers the phone when it rings, and then disconnects after a given time. the code is below, hope it is of some use.


####Code Below####

Option Explicit
Private Declare Function WritePrivateProfileString Lib "Kernel32" Alias "WritePrivateProfileStringA" (ByVal lpApplicationName As String, ByVal lpKeyName As Any, ByVal lpString As Any, ByVal lpFileName As String) As Long
Private Declare Function WritePrivateProfileSection Lib "Kernel32" Alias "WritePrivateProfileSectionA" (ByVal lpAppName As String, ByVal lpString As String, ByVal lpFileName As String) As Long
Private Declare Function GetPrivateProfileString Lib "Kernel32" Alias "GetPrivateProfileStringA" (ByVal lpApplicationName As String, ByVal lpKeyName As Any, ByVal lpDefault As String, ByVal lpReturnedString As String, ByVal nSize As Long, ByVal lpFileName As String) As Long


Private Sub ListenForRing()

' Buffer to hold input string
Dim DataString As String
Dim rc As Long

DataString = String(255, 0)

Dim Instring As String
Dim Comm_Baud As String
Dim Comm_Port As Integer
Dim Comm_Parity As String
Dim Comm_Data As String
Dim Comm_Stop As String
Dim Comm_Rings As String
Dim Comm_Buffer As Integer

rc = GetPrivateProfileString("COMMS", "PORT", "3", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Port = Val(DataString)
rc = GetPrivateProfileString("COMMS", "BAUD", "4800", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Baud = Trim$(Str$(Val(DataString)))
rc = GetPrivateProfileString("COMMS", "PARITY", "n", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Parity = Left$(DataString, 1)
rc = GetPrivateProfileString("COMMS", "DATA BIT", "8", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Data = Trim$(Str$(Val(DataString)))
rc = GetPrivateProfileString("COMMS", "STOP BIT", "1", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Stop = Trim$(Str$(Val(DataString)))
rc = GetPrivateProfileString("COMMS", "RINGS", "1", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Rings = Trim$(Str$(Val(DataString)))
rc = GetPrivateProfileString("COMMS", "BUFFER", "22", DataString, 10, "C:\windows\MODEMANS.INI")
Comm_Buffer = Val(DataString)

'Comm_Baud "," + Comm_Port + "," + Comm_Parity + "," + Comm_Data + "," + Comm_Stop

' Use COM1.
MSComm1.CommPort = Comm_Port
' 9600 baud, no parity, 8 data, and 1 stop bit.
MSComm1.Settings = Comm_Baud + "," + Comm_Parity + "," + Comm_Data + "," + Comm_Stop '"4800,N,8,1"
' Tell the control to read entire buffer when Input
' is used.
MSComm1.InputLen = 0
' Open the port.
MSComm1.PortOpen = True
' Send the attention and answer on first ring commands to the modem.
MSComm1.Output = "AT S0=" + Comm_Rings + Chr$(13)
' Wait for data to come back to the serial port.

Do
DoEvents
Loop Until MSComm1.InBufferCount >= Comm_Buffer

' Read the "OK" response data in the serial port.

Instring = MSComm1.Input

Timer1.Enabled = True
End Sub

Private Sub cmdQuit_Click()
End
End Sub

Private Sub Form_Load()


Dim DataString As String
Dim rc As Integer
'Get value for timer (in seconds)

If App.PrevInstance = True Then
MsgBox "Program already running.", vbCritical, "Modem Answer"
End
End If

DataString = String(255, 0)

rc = GetPrivateProfileString("TIMING", "ANSWERTIME", "<no file>", DataString, 10, "C:\windows\MODEMANS.INI")
If Val(DataString) < 1 Then
rc = WritePrivateProfileString("TIMING", "ANSWERTIME", "55", "C:\windows\MODEMANS.INI")

rc = WritePrivateProfileString("COMMS", "PORT", "3", "C:\windows\MODEMANS.INI")
rc = WritePrivateProfileString("COMMS", "BAUD", "4800", "C:\windows\MODEMANS.INI")
rc = WritePrivateProfileString("COMMS", "PARITY", "n", "C:\windows\MODEMANS.INI")
rc = WritePrivateProfileString("COMMS", "DATA BIT", "8", "C:\windows\MODEMANS.INI")
rc = WritePrivateProfileString("COMMS", "STOP BIT", "1", "C:\windows\MODEMANS.INI")

rc = WritePrivateProfileString("COMMS", "RINGS", "1", "C:\windows\MODEMANS.INI")
rc = WritePrivateProfileString("COMMS", "BUFFER", "22", "C:\windows\MODEMANS.INI")

rc = GetPrivateProfileString("TIMING", "ANSWERTIME", "<no file>", DataString, 10, "C:\windows\MODEMANS.INI")

End If
Timer1.Interval = Val(DataString) * 1000

'Start program running with timer value got from INI
ListenForRing
End Sub



Private Sub Timer1_Timer()
' Close the serial port.
MSComm1.PortOpen = False
'Switch off timer
Timer1.Enabled = False

'Restart program
ListenForRing


End Sub