Option Explicit

'**********************************************************************

'* S2L7.bas - (Section 2, Lesson 7) RECEIVING DATA FROM THE ALL CHANNEL

'*            This is the RTDX Host Client for Section 2, Lesson 7

'*

'* This example receives integer values 1-3 from the target via the

'* ALL channel

'**********************************************************************



Const Success = &H0                     ' Method call is valid

Const Failure = &H80004005              ' Method call failed

Const ENoDataAvailable = &H8003001E     ' No data was available.

                                        ' However, more data may be

                                        ' available in the future.

Const EEndOfLogFile = &H80030002        ' No data was available

                                        ' The end of the log file has

                                        ' been reached.





Sub main()



    Dim rtdx As Object

    Dim data As Long

    Dim status As Long

    Dim i As Long



    On Error GoTo Error_Handler



    ' Create an instance of the RTDX COM object

    Set rtdx = CreateObject("RTDX")



    '******************************************************************

    ' Insert code from Step #3 here - to open the "ALL" channel for

    '                                 reading

    '******************************************************************

    status = rtdx.Open("ALL", "R")



    If status <> Success Then

        Debug.Print "Opening of channel ALL failed"

        GoTo Error_Handler

    End If



    Do

        ' Read a 32-bit integer from the target

        status = rtdx.ReadI4(data)

        

        Select Case (status)

            Case Success

                If status = Success Then

                    Debug.Print "Value " & _

                                data & _

                                " was received from the target"

                End If

            Case ENoDataAvailable

                Debug.Print "No data is currently available"

            Case EEndOfLogFile

                Debug.Print "End of log file has been detected"

            Case Failure

                Debug.Print "ReadI4 returned failure"

                Exit Do

            Case Else

                Debug.Print "Unknown return code"

                Exit Do

        End Select

    Loop Until status = EEndOfLogFile



    ' Close the channel

    status = rtdx.Close()



    ' Release the reference to the RTDX COM object

    Set rtdx = Nothing



    Exit Sub



Error_Handler:

Debug.Print "Error in COM method call"

Set rtdx = Nothing



End Sub