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| The aim of this exercise is to demonstrate the use of analogue input devices within a Flowcode flowchart.
| | For an excellent introduction guide, we recommend [https://www.flowcode.co.uk/education/ Introduction to microcontroller programming] |
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| Digital inputs are simpler to deal with, as they have a finite range of possible values.<br />
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| For example, a two bit digital input can have one of only four possible values - 00, 01, 10 or 11.<br /> | |
| Flowcode uses an 'Input' icon [[File:Btn Input.gif|30px]] to deal with digital inputs.
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| An analogue input, on the other hand can have any of an infinite number of possible values.<br />
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| As a result, it is more difficult to handle in Flowcode.
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| [[File:gen_exerciseUsingAnInp_ansyspan_01.png|300px|right]]
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| A component macro [[File:Btn Component Macro.gif|30px]] is used to input data from an analogue sensor.<br />
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| The data is then stored in a variable.
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| Component macros are sections of code that have been written to support the components included with Flowcode 6.<br />
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| They take all the effort out of using these components.
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| In this exercise, a warning lamp lights when the signal from an ADC dial device rises too far.
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| __TOC__
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| ==The flowchart sequence==
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| The flowchart will:
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| ::::* Read the value set on the input device, the ADC dial.
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| ::::* Compare this with a set value, and:
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| ::::: if greater than the set value, turn on a lamp;
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| ::::: if less, then make sure that the lamp is off.
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| ::::* Loop back to the beginning, and repeat the process.
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| ==Create the 'input' variable==
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| :* In the 'Edit' menu, on the main toolbar, click on 'Variables...' to open the [[Variable Manager]] dialogue box.
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| ::* Hover just to the left of the 'Variables' label, and click on the down arrow that appears.
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| ::* Select 'Add new' and the 'Create a New Variable' dialogue box opens.
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| ::* Name the new variable "input".
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| ::* Leave the variable type as 'Byte'.
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| ::* Click on 'OK'.
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| ::* The dialogue box is shown opposite.
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| ==Create the flowchart==
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| * Click and drag an infinite loop, [[File:Btn Loop.gif|30px]] between the 'BEGIN' and 'END' icons.
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| [[File:gen_exerciseUsingAnInp_ancompmacprop_01.png|300px|right]]
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| * Inside the loop:
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| :* Click and drag a 'Component macro' icon.[[File:Btn_Component_Macro.gif|30px]]
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| ::* Double click on it to open the dialogue box, so that you can configure it.
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| ::: The program 'knows' which components you have added to the System or Dashboard panel, and modifies the list of available commands accordingly.
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| ::: Under 'Components', the ADC dial will be listed, and underneath it the list of commands.
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| ::* Scroll down the list and click on the 'GetByte' command.
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| ::: This reads the output of the analogue input device - the ADC dial in this case, and stores it in the byte variable called 'input'.
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| ::* Rename the 'Display name' as "Read the input".
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| ::* Click on 'OK'.
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| ::* Again, the dialogue box is shown opposite.
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| * Next, drag and drop a 'Decision' box, [[File:Btn Decision.gif|30px]] and double click on it to open the dialogue box.
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| [[File:gen_exerciseUsingAnInp_andecprop_01.png|300px|right]]
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| :* Rename it "Compare it !"
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| :* In the condition 'If' box, type "input>128".
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| :: The '128' is totally arbitrary in this program. A byte variable can store any value from 0 to 255, so 128 is roughly half way.
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| :: In this case, the program decides whether the value stored in the variable 'input' is greater or smaller than 128, and reacts differently depending on that decision.
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| :* Click on 'OK'.
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| ::* Again, the resulting dialogue box is shown opposite.
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| [[File:gen_exerciseUsingAnInp_anoutprop0_01.png|300px|right]]
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| * In the 'Yes' branch, drag and drop an 'Output' icon, [[File:Btn Output.gif|30px]].
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| :* Double click on it to open the dialogue box.
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| :* Change the 'Display name:' to "Switch on the lamp".
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| :* In the 'Variable or value:' box, type "1".
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| :* Configure the rest of the box to output this to 'PORT A' 'Single Bit:' 0.
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| :* Click on 'OK'.
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| [[File:gen_exerciseUsingAnInp_anoutprop1_01.png|300px|right]]
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| * In the 'No' branch, drag and drop a second 'Output' icon.
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| :* Double click on it to open the dialogue box.
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| :* Change the 'Display name:' to "Switch off the lamp".
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| :* In the 'Variable or value:' box, type "0".
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| :* Configure the rest of the box to output this to 'PORT A' 'Single Bit:' 0.
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| :* Click on 'OK'.
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| ::* Again, the dialogue boxes for the 'Output' icons are shown opposite.
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| The flowchart should now resemble the one shown below.
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| [[File:gen_exerciseUsingAnInp_anprog_01.png|300px|center]]
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| ==Add the LED==
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| * Locate the 'Single LED' in the 'Outputs' toolbox in the [[Tools and Views#1) Icons Toolbar|Icons toolbar]].
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| :* Hover over the image to the left of the 'Single LED' label, and click on the down-arrow that appears.
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| :* Click on the 'Add to system panel' option to select it.
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| :* Select the LED on the System panel and drag it to a suitable position.
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| :* Look at the Panel Properties, the 'Connection' property shows that, by default, it is connected to Port A, bit 0.
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| :: Leave it like this.
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| ==Add the ADC dial==
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| The ADC dial represents a number of input devices.
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| * Locate the 'ADC dial' in the 'Inputs' toolbox in the [[Tools and Views#1) Icons Toolbar|Icons toolbar]].
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| :* Hover over the image to the left of the label, and click on the down-arrow that appears.
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| :* Click on the 'Add to system panel' option to select it.
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| :* Select the ADC dial on the System panel and drag it to a suitable position.
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| :* Look at the Panel Properties, and locate the 'Connection' property. Just below it, the 'Channel' property shows that, by default, it is connected to 'AN0' - the first bit of the microcontroller capable of accepting an analogue input. Click on 'AN0' to open a pinout of the microcontroller.
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| ::* Click on the rectangle representing input 'AN1' to change the connection to this channel.
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| :: Leave it like this.
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| ==Final testing==
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| * Save the flowchart as 'Analogue,fcf'.
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| * Click on the simulation button [[File:Btn Run.png|30px]].
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| * Use the mouse to turn the pointer on the ADC dial, and notice what happens when you pass the half-way mark.
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| * Click on the 'Stop simulation' button, [[File:Btn Stop.png|30px]] when you are happy with the program's behavior.
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