modi123_1, on 16 May 2013 - 09:24 AM, said:

Not only human finger we can called it as pointer similar to old style projector pointer stick. with some color identification on its tip.

dbasnett, on 02 July 2011 - 07:43 AM, said:

I am using VB .Net's IO.Ports.SerialPort it just named as mscomm because trying to port code from vb6 to vb.net...
What does it make difference to my question...

Following code is from frmMain to send command to hardware mscomm is class which write command to serial port and handle response from serial port
frmMain

Dim gresponse() As Byte

[1]mscomm.fnReadHoldingRegisters(1, 58, 8, Val(txtTimeOut.Text))
[2]gresponse = mscomm.getResponse
[3]        Try
[4]            lblReference1.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(0), gresponse(1)).ToString())
[5]            lblReference2.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(2), gresponse(3)).ToString())
[6]            lblReference3.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(4), gresponse(5)).ToString())
[7]            lblReference4.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(6), gresponse(7)).ToString())
[8]            lblReference5.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(8), gresponse(9)).ToString())
[9]            lblReference6.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(10), gresponse(11)).ToString())
[10]            lblReference7.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(12), gresponse(13)).ToString())
[11]            lblReference8.Text = mscomm.fnGet2Compliment(mscomm.fnGetHexVal(gresponse(14), gresponse(15)).ToString())
[12]        Catch ex As Exception
[13]            lblNote.Text = "Fail"
[14]            fail = fail + 1
[15]        End Try

clsMscomm write command function

    Private Function fnReadHoldingRegisters(ByVal SlaveNumber As Integer, ByVal fromAddr As Double, ByVal numberOfRegisters As Double, ByVal RegisterType As Integer, Optional ByVal timeOut As Double = 250) As Boolean

        fnInitCommunication(numberOfRegisters * 2 + PROTOCOL_CONST_PADDING, RegisterType, SlaveNumber, fromAddr, numberOfRegisters, timeOut)
        WriteToPort(fnFormCommand(""))

Once WriteToPort get executed following function handle response

Private Sub MSComm1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles MSComm1.DataReceived
[1]        Dim buff As String
[2]        buff = MSComm1.ReadExisting
[3]        'Combine previous response and new response
[4]        inbuffor = inbuffor & buff
[5]        'Calculate expected length
[6]        cnt = cnt - Len(buff)
[7]        'If expected response reached then validate response
[8]        If cnt = 0 Then
[9]            If fnValidateResponse(inbuffor) = True Then flValidResponse = True
[10]            'Latch help to come out response waiting loop. False means wait, True means come out.
[11]            flLatchOpen = True
[12]        End If
[13]    End Sub

OK.
now the problem is when WriteToPort complete its work we receive some bytes at MSComm1_DataReceived and two function first one from frmMain and other one MSComm1_DataReceived start executing statement one by one like statement no 2 from frmMain after that statement no 3 from MSComm1_DataReceived and so on until one of them finish in statements.

i dont understand this type of behavior frmMain should wait until MSComm1_DataReceived finish its work.

modi123_1, on 01 July 2011 - 05:45 AM, said:

Sorry "i click on submit topic and it is taking huge time hence i refresh page and again click on submit button with new name that is how two topics are there..."

Thanks guys it really help....