Temperature Strip Chart

Assigned activities

In this activity you will use a Custom Control called a Strip Chart which visually displays a sensor's output in real time as a moving Graph. You need to make sure the Strip Chart controled is installed on your computer!

Activity 1
Part 1

Required Resources

  • Phidget IFKit 888
  • Precision Temperature Sensor

Circuit Configuration

Plug the temperature sensor into Analog Input port 0. Plug the 888 Interface kit into the computer via a USB cable.

Create the Graphical User Interface

Note: Save your project at frequent intervals!

Run Visual Basic 6.  Select a Standard Exe.

  • Draw a Frame on the form.
     
  • Draw the following control on the frame.
    • A Timer
    • A Textbox
  • Open the Project menu and select Components.
  • Scroll down to and select GMS Strip Chart ActiveX Control. Note: you must click the box so that the check mark appears. Click OK

  • Look at the bottom of the tool bar. A new control should be added. Select and draw the strip chart on the frame. Note: If you get a permission denied error, an administrator has to log in and do the exact same steps once. Then it will work for everyone else using the computer.

Change the properties for the following:

  • Frame1
    • Caption - Temperature Monitor
    • Font - Arial, 14pt, bold
    • Backcolor - something appropriate
       
  • Timer1
    • Interval - 1000
  • Text1
    • Font Bold, 14 size
  • Strip1
    • Backcolor - You pick something!
    • Trackmax - 40
    • Trackmin - -50 (negative 50)
    • TrackDisplayMax - 40
    • TrackDisplayMin - -50
    • VariableLineWidth - 3
    • VariableColor - Red

Code the Interface

  • You will be using the Phidget IFKit 888 therefore the Phidget library must be referenced. Open the Project menu and select References.

    Scroll down and check Phidget Library 2.1. Click OK.
     
  • Open the code window. Start by selecting General...Declarations in the small windows. Enter the following code:

Dim WithEvents kit As PhidgetInterfaceKit

  • Code the Form_Load procedure:

Set kit = New PhidgetInterfaceKit
Call kit.Open

  • Code the Timer1 procedure with:

temp = (kit.SensorValue(0) * 0.2222) - 61.111
Strip1.Y = temp
Strip1.Redraw
Text1 = temp
Text1.Refresh

Test the System

Save your project. Run the program. You should see the temperature displayed in the text box and the strip chart starting to display the data. Warm up the sensor by touching it. You can safely cool the sensor by using a can of compresses "air" used to clean LCD screens and laptops. Invert the can and spray the sensor. Keep your fingers out of the way as the temperature can reach -50C!

Challenge

Take a remote temperature reading. That is, connect the phidget and sensor to another computer on your network. You will need to know the IP address of the computer with the Phidget and sensor attached. Also make sure the Phidget Web Service is running on the remote computer. If you are not an administrator, your teacher will have to do that.

Hint: The only change needed in code is in the form load procedure. Here is an example. Let's say the remote computer has an ip address of 192.168.1.110. Modify the line:

Call kit.Open

to

Call kit.OpenRemoteIP("192.168.1.110", 5001)

Note: The IP address must be in quotation marks. 5001 is the default port used by the Phidget web service.

 
2004 CDLI