Exercise - Create an LED Component

Creating a graphic

• Open a new Flowcode flowchart.

• Make sure that the System Panel and Properties Panel are visible.

• If they are not, then select them in the View Menu.

• Click on the hemisphere shape in the Shapes menu and drag one onto the Systems Panel.

File:Panel Toolbar Shapes3D.png

• The blue dotted square around it shows that this object is currently selected.

• Change the name of the component to 'LEDcomponent'.

To do this:

• Find the 'handle' of the component at the top of the Panel Properties.
• Click on the name 'shape' (the default name).
• Change it to 'LEDcomponent'.

Adding properties

• Next, add two properties to the LED. The first allocates a color. The second sets up a connection from the LED to the controlling microcontroller.

• First add a default color to the component, using a new property called 'color'.

To do this:

• De-select the hemisphere by clicking anywhere outside it in the Systems Panel.
• Hover over the icon to the right of the 'Properties' label.
• Click on the down-arrow that appears.
• Click on 'Add new'.
• In the 'Cosmetic name' box type "LEDcolor".
• Select 'Color picker' for the 'Property type'.
• Type "color" for the 'Property variable' name.

• In the same way, then add another new property to specify the default connection. Give it a Cosmetic name "Connection", with Property type 'Single digital pin' and a Property variable name "pin".

• Finally, configure these properties. To do this:

• Click on the color shown for the 'color' property.

  

• Select a color from the color chart that appears.
• Click on the word 'Unconnected', alongside the 'pin' property.
• Select an appropriate pin, such as RA0, from the chip pin layout.

Reacting when a pin changes state

First, create a pin change macro. The Property change event is triggered when any property you have added to your component changes.

• Open the Project Explorer from the View menu.

• Double-click on the item 'Connection -> PinChange'. The 'Add event' dialogue box opens.

• Hover over the icon to the left of the 'Macro' label. A drop-down arrow appears.

• Click on the arrow and select the option 'Add new'. The 'Edit Macro Details' dialogue box opens.

• Change the name of the macro to 'PinChange'.

• Click on 'OK'.

Next, set up the 'PinChange' macro.

• Select 'Show as Flowchart' from the 'Macro' menu, and choose the 'PinChange' macro.

Add the following details:

• Add a Decision icon to the PinChange

Updating when a pin changes

Because your component is connected to a pin, you want to run a flowchart when that pin changes. To do this, you can use the PinChange event.

To complete