Assistance Required with VB.net

[LEDave]

Hi,

I'm trying to send data from PIC - PC using the program mackrackit pointed to earlier in this thread.

http://www.rentron.com/receiving_data.htm

When I compile it I have this error message: Name 'comEvReceive' is not declared.

Does anyone have an idea of a fix (with as much of an explaination as you can spare please, I'm new to this). I've done lots of Googling with various answer from 'Select Case' to it can't be done in the 2008 VB-Version.

 Private Sub MSComm1_OnComm()
Dim sData As String ' Holds our incoming data
Dim lHighByte As Long   ' Holds HighByte value
Dim lLowByte As Long    ' Holds LowByte value
Dim lWord As Long       ' Holds the Word result

' If comEvReceive Event then get data and display
If MSComm1.CommEvent = comEvReceive Then

    sData = MSComm1.Input ' Get data (2 bytes)
    lHighByte = Asc(Mid$(sData, 1, 1)) ' get 1st byte
    lLowByte = Asc(Mid$(sData, 2, 1))  ' Get 2nd byte
    
    ' Combine bytes into a word
    lWord = (lHighByte * &H100) Or lLowByte
    
    ' Convert value to a string and display
    lblRCTime.Caption = CStr(lWord)
    
End If
End Sub

I guess I should add I'm using Visual Basic 2008 Express Edition.

Any help much appreciated.

Dave

[gadelhas]

Hi,

I guess I should add I'm using Visual Basic 2008 Express Edition.

Dave

Hi,

The code posted is VB6 and you are using VB2008.
Try the code in the post 9, of this thread!

[LEDave]

Here's my attempt to modify the code from gadelhas's post above. My FORM has two push buttons, one opens the COM1 PORT the other closes it. I can't get it to show any data in the ListBox1 though from the PIC. The PIC code (shown below) outputs a RANDOM BYTE.

Any Ideas? Anyone?

Public Class Form1
    Dim WithEvents SerialPort1 As New IO.Ports.SerialPort
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        SerialPort1.PortName = "COM1"
        SerialPort1.Parity = IO.Ports.Parity.None
        SerialPort1.BaudRate = 2400
        SerialPort1.DataBits = 8
        SerialPort1.StopBits = 1
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If SerialPort1.IsOpen = False Then SerialPort1.Open()
        If SerialPort1.IsOpen = True Then MsgBox("com1 port opened sucessfully")
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        If SerialPort1.IsOpen = True Then SerialPort1.Close()
        If SerialPort1.IsOpen = False Then MsgBox("com1 port closed sucessfully")

    End Sub

    Private Sub DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
        Dim recepcao As String

        recepcao = SerialPort1.ReadExisting



    End Sub


    Private Sub ListBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListBox1.SelectedIndexChanged
        SerialPort1.Write(ListBox1.Text)

PIC code:

A VAR WORD
X VAR WORD
Y VAR WORD
Z VAR BYTE

main:
Random A
Y = A * 100
X = DIV32 25700
LET Z = X

SEROUT2 PORTC.3, 16780, [DEC z, 10, 13]
pause 4000
GOTO MAIN

[LEDave]

Here's another program which does receive the same data from the PIC. Only it displays it vertically instead of in BYTES across the ListBox. Anyone know how to modify this to display the BYTES properly?

This is how the data appears in the ListBox v's the serial Communicator which displays them properly.

VB has the numbers
1
3
5
*
*
2
0
3
*
And Serial Communicator has them
135
203

Here's the program, this maybe the one to adapt / work on as it's nearly there:

Imports System
Imports System.ComponentModel
Imports System.Threading
Imports System.Windows.Forms


Public Class Form1


    'Buffer for receievd data***

    Private Delegate Sub AddListBoxItemInvoker(ByVal item As Object)


    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        SerialPort1.PortName = "COM1"
        SerialPort1.Parity = IO.Ports.Parity.None
        SerialPort1.BaudRate = 2400
        SerialPort1.DataBits = 8
        SerialPort1.StopBits = 1

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        If SerialPort1.IsOpen = False Then SerialPort1.Open()
        If SerialPort1.IsOpen = True Then MsgBox("com1 port opened sucessfully")

    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        If SerialPort1.IsOpen = True Then SerialPort1.Close()

        If SerialPort1.IsOpen = False Then MsgBox("com1 port closed sucessfully")

    End Sub

    

    Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived

        Me.AddListBoxItem(SerialPort1.ReadExisting)


    End Sub

    Private Sub AddListBoxItem(ByVal item As Object)

        If Me.ListBox1.InvokeRequired Then
            'We are on a secondary thread so delegation is required.
            Me.ListBox1.Invoke(New AddListBoxItemInvoker(AddressOf AddListBoxItem), (item))

        Else
            'We are on the primary thread so add the item.
            Me.ListBox1.Items.Add(item)
        End If
    End Sub
End Class

Thanks for any help.

Dave

[HenrikOlsson]

Hi Dave,
When you use something like this (and z is 135):

SEROUT2 PORTC.3, 16780, [DEC z, 10, 13]

The PIC actually sends 5 bytes, not one (or three). It sends "1", "3", "5", (CR), (LF) that's why your VB program displays them one by one (because you read them from the serial buffer one by one).

What is being sent is the ASCII codes for the digits 1,3,5 so what is actually being transmitted is 49, 51, 53, 10, 13 where 49 means the digit 1, 51 means the digit 3 and so on.

If you remove the DEC modifer what is being sent is three bytes ie. 135,10,13 but now it's likely the VB program will fill the listbox with a little c with a hook below it (the character that corresponds to ASCII code 135).

If you want the number (135) to be a "value" in VB (and not one or more text strings) then you need to read it as such - or convert it. My VB isn't up to speed (never has been) but I think there's something like

DIM myValue as Integer
myValue = SerialPort1.ReadByte
 ' OR
myValue = SerialPort1.ReadChar

Then you populate your listbox with something like

Me.AddListBoxItem(myValue.ToString)

In this case the ToString basically does for VB what the DEC modifer does for PBP, ie. it converts the value of 135 (a single byte) into the ASCII representation of each digit, "1", "3", "5".

My VB syntax may not be correct in this example but I think you get the gist of it.

/Henrik.

[LEDave]

Hi Henrik,

Thanks for that as ever.

Really good explanation there. I'll have a look at it this evening and try and get it working properly.

Again many thanks.

Dave

[LEDave]

Hi Henrik,

Success, but..........!

First of all the success. I changed the PIC code to:

SEROUT2 PORTC.3, 16780, [ z]

Then changed this line in the VB program:

 Me.AddListBoxItem(SerialPort1.ReadExisting)

To:

Me.AddListBoxItem(SerialPort1.ReadByte)

And away it went reading and displaying Random Bytes, brilliant

Now for the but part. I actually want the VB program to read a WORD sent from the PIC (a short in VB?) however for the AddListBoxItem(SerialPort1.Readxxxx there is:

ReadByte
ReadChar
ReadExisting
ReadLine
ReadTo

No ReadShort

Now I'm thinking somehow it's send a High Byte from the PIC then a Low Byte and join them together in VB, unless there's a 'ReadShort' option.

Dave