[RESOLVED] Converting voltage level into graphical display

[catherine0136]

Thanks for helping ! =)

Am i right to place the VoltsQ.Count>2 as follows, please correct me if i'm wrong.

If VoltsQ.Count > 2

 'Put your code for drawing the axes etc. here.


            'Details of the graph layout -- fill in your own values here!
            Dim Origin As New Point(50, 119)
            Dim xAxisLength As Integer = 210
            Dim yAxisLength As Integer = -120

            'Turn the queue into an array:
            Dim voltsQarray As Single() = voltsQ.ToArray

            'Define an array of data points:
            Dim DataPoints(voltsQ.Count - 1) As Point
            Dim x, y As Integer

            'Fill in the array using the voltage readings:
            For i As Integer = 0 To voltsQ.Count - 1
                'Get the volts value from the queue:
                Dim v As Single = voltsQarray(i)
                'Find the distance along the x axis:
                x = Origin.X + CInt(i * xAxisLength / 40)
                'find the height of the data point on the Y axis:

                y = Origin.Y + CInt(v * yAxisLength / maxVolts)
                'Put the point in the array
                DataPoints(i) = New Point(x, y)

            Next
            'Draw the waveform:        
            e.Graphics.DrawCurve(Pens.Green, DataPoints)

        End If

Btw, after placing all the code into the program, this is what i observe [ please see attached image ] Hmm.. its still a straight line though but it is varying quantity against time. So i believe its correct ?

[boops boops]

Thanks for helping ! =)
Am i right to place the VoltsQ.Count>2 as follows, please correct me if i'm wrong.

That should work, but it would be neatest to put it after drawing the axes. That way they will still show when there is no signal. It must come before you define voltsQarray.

Btw, after placing all the code into the program, this is what i observe [ please see attached image ] Hmm.. its still a straight line though but it is varying quantity against time. So i believe its correct ?

It's not what I would expect if everything is working properly. There might be something wrong in the code, but you should try to eliminate other possibilities. What happens when you change the light on the solar cell? What happens to the line when you disconnect the solar cell or the RS232 interface? And what happens when you type a different value in the textbox?

BB

[catherine0136]

It's not what I would expect if everything is working properly. There might be something wrong in the code, but you should try to eliminate other possibilities. What happens when you change the light on the solar cell? What happens to the line when you disconnect the solar cell or the RS232 interface? And what happens when you type a different value in the textbox?

Originally, it shows a straight line because it is taking the voltage from the "Average Voltage" textbox.

I edited so that i'll let the waveform follow the voltage from the "Voltage Level in Volts(V)" textbox, in which the voltages displayed in "Voltage Level in volts varies greatly from 2.30V to slightly above 3.0V, and the waveform will be like this (see attached image - Solar Cell).

When my hand is place over the solar cell, i am able to observe that the voltage level will decrease and the waveform will also move lower. (See attached image - Solar Cell 1)

Is it whole waveform correct?

I'll attached the coding which i insert into my program in the next thread.

[catherine0136]

Following is the code of PictureBox2, to display the waveform.

Private Sub PictureBox2_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles PictureBox2.Paint

        Dim g As Graphics = e.Graphics
        Dim vertFont As New Font("Verdana", 10, FontStyle.Bold)
        Dim horzFont As New Font("Verdana", 10, FontStyle.Bold)
        Dim vertBrush As New SolidBrush(Color.Blue)
        Dim horzBrush As New SolidBrush(Color.Blue)
        Dim horzBrush1 As New SolidBrush(Color.Blue)

        Dim BluePen As New Pen(Color.Blue)

        ' Drawing a vertical and a horizontal line 
        g.DrawLine(BluePen, 50, 225, 50, 15)   'vertical line
        g.DrawLine(BluePen, 50, 120, 260, 120)  'horizontal line


        'Details of the graph layout 
        Dim Origin As New Point(50, 119)
        Dim xAxisLength As Integer = 210
        Dim yAxisLength As Integer = -120

        If voltsQ.Count > 2 Then

            'Turn the queue into an array:
            Dim voltsQarray As Single() = voltsQ.ToArray

            'Define an array of data points:
            Dim DataPoints(voltsQ.Count - 1) As Point
            Dim x, y As Integer

            'Fill in the array using the voltage readings:
            For i As Integer = 0 To voltsQ.Count - 1
                'Get the volts value from the queue:
                Dim v As Single = voltsQarray(i)
                'Find the distance along the x axis:
                x = Origin.X + CInt(i * xAxisLength / 40)
                'find the height of the data point on the Y axis:

                y = Origin.Y + CInt(v * yAxisLength / maxVolts)
                'Put the point in the array
                DataPoints(i) = New Point(x, y)

            Next
            'Draw the waveform:        
            e.Graphics.DrawCurve(Pens.Green, DataPoints)

        End If


        'Draw vertical strings 
        Dim vertStrFormat As New StringFormat()
        vertStrFormat.FormatFlags = StringFormatFlags.DirectionVertical
        g.DrawString("-", horzFont, horzBrush, 49, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 49, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 59, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 69, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 79, 113, vertStrFormat)
        g.DrawString("--", horzFont, horzBrush, 89, 106, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 99, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 109, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 119, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 129, 113, vertStrFormat)
        g.DrawString("--", horzFont, horzBrush, 139, 106, vertStrFormat)

        g.DrawString("-", horzFont, horzBrush, 149, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 159, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 169, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 179, 113, vertStrFormat)
        g.DrawString("--", horzFont, horzBrush, 189, 106, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 199, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 209, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 219, 113, vertStrFormat)
        g.DrawString("-", horzFont, horzBrush, 229, 113, vertStrFormat)
        g.DrawString("--", horzFont, horzBrush, 239, 106, vertStrFormat)


        ' y-axis drawing 

        g.DrawString("  4 --", vertFont, vertBrush, 25, 12)
        g.DrawString("    --", vertFont, vertBrush, 25, 12)
        g.DrawString("     -", vertFont, vertBrush, 25, 17)
        g.DrawString("     -", vertFont, vertBrush, 25, 22)
        g.DrawString("     -", vertFont, vertBrush, 25, 27)
        g.DrawString("     -", vertFont, vertBrush, 25, 32)

        g.DrawString("  3 --", vertFont, vertBrush, 25, 37)
        g.DrawString("    --", vertFont, vertBrush, 25, 37)
        g.DrawString("     -", vertFont, vertBrush, 25, 42)
        g.DrawString("     -", vertFont, vertBrush, 25, 47)
        g.DrawString("     -", vertFont, vertBrush, 25, 52)
        g.DrawString("     -", vertFont, vertBrush, 25, 57)

        g.DrawString("  2 --", vertFont, vertBrush, 25, 62)
        g.DrawString("    --", vertFont, vertBrush, 25, 62)
        g.DrawString("     -", vertFont, vertBrush, 25, 67)
        g.DrawString("     -", vertFont, vertBrush, 25, 72)
        g.DrawString("     -", vertFont, vertBrush, 25, 77)
        g.DrawString("     -", vertFont, vertBrush, 25, 82)

        g.DrawString("  1 --", vertFont, vertBrush, 25, 87)
        g.DrawString("    --", vertFont, vertBrush, 25, 87)
        g.DrawString("     -", vertFont, vertBrush, 25, 92)
        g.DrawString("     -", vertFont, vertBrush, 25, 97)
        g.DrawString("     -", vertFont, vertBrush, 25, 102)
        g.DrawString("     -", vertFont, vertBrush, 25, 107)
        g.DrawString("  0", vertFont, vertBrush, 25, 112)

        g.DrawString("     -", vertFont, vertBrush, 25, 117)
        g.DrawString("     -", vertFont, vertBrush, 25, 122)
        g.DrawString("     -", vertFont, vertBrush, 25, 127)
        g.DrawString("     -", vertFont, vertBrush, 25, 132)
        g.DrawString("    --", vertFont, vertBrush, 25, 137)
        g.DrawString(" -1--", vertFont, vertBrush, 25, 137)

        g.DrawString("     -", vertFont, vertBrush, 25, 142)
        g.DrawString("     -", vertFont, vertBrush, 25, 147)
        g.DrawString("     -", vertFont, vertBrush, 25, 152)
        g.DrawString("     -", vertFont, vertBrush, 25, 157)
        g.DrawString("    --", vertFont, vertBrush, 25, 162)
        g.DrawString(" -2--", vertFont, vertBrush, 25, 162)

        g.DrawString("     -", vertFont, vertBrush, 25, 167)
        g.DrawString("     -", vertFont, vertBrush, 25, 172)
        g.DrawString("     -", vertFont, vertBrush, 25, 177)
        g.DrawString("     -", vertFont, vertBrush, 25, 182)
        g.DrawString("    --", vertFont, vertBrush, 25, 187)
        g.DrawString(" -3--", vertFont, vertBrush, 25, 187)

        g.DrawString("     -", vertFont, vertBrush, 25, 192)
        g.DrawString("     -", vertFont, vertBrush, 25, 197)
        g.DrawString("     -", vertFont, vertBrush, 25, 202)
        g.DrawString("     -", vertFont, vertBrush, 25, 207)
        g.DrawString("    --", vertFont, vertBrush, 25, 212)
        g.DrawString(" -4--", vertFont, vertBrush, 25, 212)

        ' Dispose of objects 
        vertFont.Dispose()
        horzFont.Dispose()
        vertBrush.Dispose()
        horzBrush.Dispose()
        BluePen.Dispose()

        'Display text in Y-axis
        Dim Font1 As New Font("Comic Sans MS", 10, FontStyle.Bold)
        g.TranslateTransform(30, 148)
        g.RotateTransform(180)
        g.DrawString("Volts (V)", Font1, _
          Brushes.Blue, 0, 0, New StringFormat(StringFormatFlags.DirectionVertical))

    End Sub

Following is the coding for the timer.
I included this line, Single.TryParse(TextBoxVoltage.Text, volts1), so that the waveform will move according to the voltage shown in the "Voltage Level in Volts(V)", and not follow the average voltage(which will produce the straight line).

 Private Sub Timer3_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer3.Tick

        'read the voltage and get value from RS232 interface
        Call OpenPORT1()

        Single.TryParse(TextBoxVoltage.Text, volts1)
        'add the new reading to the end of the queue
        voltsQ.Enqueue(volts1)

        'remove the old reading at the head of the queue, to keep max. 40 data points    
        If voltsQ.Count > 40 Then voltsQ.Dequeue()

        'update the display with the new data     
        Me.Refresh()

    End Sub

As for Call OpenPORT1(),

 Private Sub OpenPORT1()
        If SerialPort1.IsOpen Then
            SerialPort1.Close()
        End If

        SerialPort1.PortName = "COM1"
        SerialPort1.BaudRate = 9600
        SerialPort1.Parity = System.IO.Ports.Parity.None
        SerialPort1.DataBits = 8
        SerialPort1.StopBits = System.IO.Ports.StopBits.One

        SerialPort1.RtsEnable = True
        SerialPort1.Open()

    End Sub

I hope everything is correct.

[catherine0136]

And as for the following:

' Drawing a vertical and a horizontal line
g.DrawLine(BluePen, 50, 225, 50, 15) 'vertical line
g.DrawLine(BluePen, 50, 120, 260, 120) 'horizontal line

 'Details of the graph layout 
        Dim Origin As New Point(50, 119)
        Dim xAxisLength As Integer = 210
        Dim yAxisLength As Integer = -120

I replaced it with a negative value. If i were to follow yours to put a positive value, the waveform will be at the negative side. I hope everything is correct. =)

[boops boops]

[catherine0136]