|
|
| (22 intermediate revisions by 5 users not shown) |
| Line 1: |
Line 1: |
| − | <sidebar>Sidebar: Controlling Electronic Devices With Flowcode</sidebar>
| + | For an excellent introduction guide, we recommend Introduction to microcontroller programming CP4375 which can be found at https://www.matrixtsl.com/learning/ |
| − | ==Program the sequence==
| |
| − | | |
| − | Now that the flowchart icons are correctly set up, we need to program them to carry out the following process:
| |
| − | :Check if the switch is pressed.
| |
| − | ::If it isn't, go back to the beginning.
| |
| − | ::If it is:
| |
| − | :::Switch on the lamp;
| |
| − | :::Wait for 10 seconds;
| |
| − | :::Switch off the lamp;
| |
| − | :::Go back to the beginning.
| |
| − | | |
| − | It takes such a short time for the microcontroller to carry this out, that we don't need to worry whether the switch latches on or not.
| |
| − | | |
| − | ==Program the input==
| |
| − | :* Double click on the [[Input Icon Properties|Input icon]].
| |
| − | :: This opens the 'Properties: Input' dialogue box, allowing you to configure the way the program treats information from the switch.
| |
| − | :: This information will be contained in a variable called 'switch'.
| |
| − | | |
| − | ::* Click on the down arrow at the right-hand end of the 'Variable:' box to open the variables dialogue box.
| |
| − | ::* Hover to the left of the 'Variables' label and click on the down arrow that appears.
| |
| − | ::* Click on the 'Add new' option to open the 'Create a New Variable' dialogue box.
| |
| − | | |
| − | ::* [[Creating Variables|Create a new variable]] named "switch" with initial value "0" and description "Copies the state of the switch"
| |
| − | ::* Leave the 'Variable type:' as 'Byte'.
| |
| − | ::: (For more information about variables, see [[Creating Variables]] and [[Variable Types]].
| |
| − | ::: (The resulting dialogue box is shown opposite.)
| |
| − | [[File:gen_exerciseFirstFlowchart_inputprops_01.png|250px|right]]
| |
| − | | |
| − | | |
| − | :* Finish configuring the input properties as follows:
| |
| − | ::* Change the 'Display name:' to "Read the switch".
| |
| − | ::* In the 'Variable:' box, type the name of the variable you created "switch".
| |
| − | ::* Leave the 'Port:' as PORT A.
| |
| − | ::* Select to 'Input from:' 'Single Bit' and choose bit 0.
| |
| − | ::: (The resulting dialogue box is shown opposite.)
| |
| − | | |
| − | [[File:Gen exerciseFirstFlowchart newvar 01.png|250px|right]]
| |
| − | | |
| − | : Set up like this, the program monitors the state of the switch, which will be connected to bit 0 of Port A of the microcontroller.
| |
| − | : When the program looks at the input switch if it is pressed, the variable 'switch' contains logic 1. If unpressed, it contains logic 0.
| |
| − | | |
| − | ==Check the Switch==
| |
| − | :* Double click on the [[Decision Icon Properties|Decision icon]] to open the configuration dialogue box, and then: [[File:gen_exerciseFirstFlowchartadddev_deciconprops_01.png|250px|right]] | |
| − | ::* Rename it "Switch pressed?".
| |
| − | ::* In the 'If:' box, type "switch=1".
| |
| − | ::* Leave the 'Swap Yes and No' box unchecked.
| |
| − | ::* Click on 'OK'.
| |
| − | | |
| − | : This will cause the program to perform what is known as a conditional branch.
| |
| − | : The subsequent course of the program depends on the outcome of the condition specified in the 'Decision' icon.
| |
| − | : In this case, it depends on whether or not the variable 'switch' = 1.
| |
| − | : If it is, the program follows the 'Yes' route. If not, it follows the 'No' route.
| |
| − | | |
| − | ==Control the Lamp==
| |
| − | : The 'No' branch is easy to set up. All we want is that the program returns to the beginning (taken care of by the 'Loop' icon.)
| |
| − | : No further configuration is needed.
| |
| − | [[File:gen_ exerciseFirstFlowchart_ outputprops_ 01.png|250px|right]]
| |
| − | | |
| − | :* Double click the 'Output' icon to open the configuration dialogue box, and then:
| |
| − | ::* Change the 'Display name:' to "Switch on".
| |
| − | ::* In the 'Variable or value:' box, type value "1".
| |
| − | ::* Change the 'Port:' to PORT B.
| |
| − | ::* Select to 'Output to: 'Single Bit' and choose bit 0.
| |
| − | ::* Click on 'OK'.
| |
| − | ::: (The resulting dialogue box is shown opposite.)
| |
| − | | |
| − | : The effect of this icon is to send a logic 1 signal (high voltage) to the lamp, connected to Port B, bit 0 of the microcontroller.
| |
| − | : This turns on the lamp.
| |
| − | | |
| − | | |
| − | : Now, we tackle the requirement that it stays on for ten seconds and then goes off.
| |
| − | [[File:gen_exerciseFirstFlowchart_delayiconprop_01.png|250px|right]]
| |
| − | * Drag and drop a 'Delay' icon after the 'Output' icon.
| |
| − | :* Double click on it to open the configuration dialogue box, and then:
| |
| − | ::* Change the 'Display name:' to "For 10 seconds".
| |
| − | ::* Change the 'Delay value:' to '10'.
| |
| − | ::* Change the unit to 'seconds'.
| |
| − | ::* Click on 'OK'.
| |
| − | ::: (Again, the resulting dialogue box is shown opposite.)
| |
| − | [[File:gen_exerciseFirstFlowchart_outputprop2_01.png|250px|right]]
| |
| − | | |
| − | | |
| − | : Finally, we need to turn off the lamp, after the ten second delay.
| |
| − | * Double click on the second 'Output' icon to allow you to configure it.
| |
| − | :*: Rename it "Switch off", and configure it to deliver value "0" to single bit 0 of Port B.
| |
| − | : The resulting dialogue box is shown opposite.
| |
| − | | |
| − | | |
| − | | |
| − | You should now [[Saving a Flowchart|save the flowchart]] as "Lamp1.fcf", and [[Closing Flowcode|close Flowcode]].
| |
| − | | |
| − | | |
| − | ==What next==
| |
| − | The next step is to add the switch and lamp to the flowchart. This is covered in the exercise [[Exercise - Adding Devices to a Program|Adding Devices to a Program]].
| |
