Understanding TotalCross for Linux ARM

Introduction
See at this guide:
Discover plugin for VS Code;
Getting your Hello World App cooler;
How to deploy; 
After basics;
Requirements
Complete the Getting Started:
Getting Started
The following electronic components are also required:
Raspberry Pi 3;
7x jumpers male-female;
Protoboard;
LED RGB module (or common 4 pins LED RGB);
Push-button module (or common push-button).
In order to execute Gpiod methods at your embedded device, you will also need to have the libgpiod-dev package installed in your board. You can do that by entering the following command at the device's terminal:
$ sudo apt-get install libgpiod-dev
Guide
Discover VS Code plugin
A quick way to start using TotalCross is installing the TotalCross extension for VS Code. 
Step 1: open VS Code console  (CTRL + Shift + P) and type TotalC… autocomplete should help!
Step 2: select TotalCross: Create new Project; 
Step 3: create a folder called HelloWorld and select it; 
Step 4: GroupId will be com.totalcross;
Step 5: ArtifactId will be HelloWorld;
Step 6: select the latest version of TotalCross SDK and -linux-arm platform;
Click to expand
Step 7: openRunHelloWorldApplication.java and click Run (IDE). The result should be:
Click  to expand
Step 8: watch the integrated simulator!
Getting your Hello World App even more Cooler 🥶
 😅
 
The following project deals with the control of an RGB LED with user interface buttons and a pin reset button!
Step 1: follow the schematic:
Step 2: to work with pin logic after public class HelloWorld extends MainWindow { add:
// Integers to store pin numbers
private int    R = 4, G = 17, B = 27, pushButton = 18;
// Integers to store state of each LED pin, 0 (LOW) and 1 (HIGH)
private int    sttR, sttG, sttB;
// Buttons to control colors 
private Button btnR, btnG, btnB;
If you need to work with different pinouts check the manufacturer manual!
Step 3: at  HelloWorld.java in initUI() code add:
// Label helloWorld made on project creation
Label helloWorld = new Label("Hello World!");
// Change the position of label on the Y axis, with TOP (beginning of Y) + a fill of 20
add(helloWorld, CENTER, TOP + 20);
Step 4: then, board setup:
// Board Setup
GpiodChip gpioChip = GpiodChip.open(0);
GpiodLine pinR = gpioChip.line(R);
GpiodLine pinG = gpioChip.line(G);
GpiodLine pinB = gpioChip.line(B);
GpiodLine pinPushButton = gpioChip.line(pushButton);
Step 5: pins setup:
// Set LED pins as outputs and default value sttX
pinR.requestOutput("CONSUMER",sttR);
pinG.requestOutput("CONSUMER",sttG);
pinB.requestOutput("CONSUMER",sttB);
// Set Reset pin as input
pinPushButton.requestInput("CONSUMER");
Step 6: the red button:
// The TotalCross button:
btnR = new Button("R");                                       // Button instantiation
                                                              // without text
btnR.setBackColor(Color.RED);                                 // Set background color (red)
btnR.addPressListener(new PressListener() {                   // Press event listener
    @Override
    public void controlPressed(ControlEvent controlEvent) {
        sttR = 1 - sttR;                                      // Invert pin state 
        pinR.setValue(sttR);                                  // Set value (HIGH or LOW)
    }
});
add(btnR, CENTER - 70, AFTER + 40);                           // To make horizontally aligned 
                                                              // buttons in the 'RGB' sequence,
                                                              // take the center reference and 
                                                              // decrease 70 to place the 
                                                              // leftmost R. In the Y axis just
                                                              // take the reference of the
                                                              // previous component and add 40
Step 7: and the other buttons: 
btnG = new Button("G");
btnG.setBackColor(Color.GREEN);
btnG.addPressListener(new PressListener() {
    @Override
    public void controlPressed(ControlEvent controlEvent) {
        sttG = 1 - sttG;                                      // Pay attention to change pin!!!
        pinG.setValue(sttG);
    }
});
add(btnG, CENTER, SAME);                                      // The green button will be 
                                                              // placed at the center and in 
                                                              // the same line of previous 
                                                              // button
​
btnB = new Button("B");
btnB.setBackColor(Color.BLUE);
btnB.addPressListener(new PressListener() {
    @Override
    public void controlPressed(ControlEvent controlEvent) {
        sttB = 1 - sttB;                                       // Pay attention to change pin!!!
        pinB.setValue(sttB);      
    }
});
add(btnB, CENTER + 70, SAME);                                  // The last button will be placed 
                                                               // to the right of the center.
Step 8: finally we use a thread to check the state of the reset button:
// A thread will be used to check every 20 ms, if the reset button has been pressed: if yes then 
// the pin state goes to LOW
new Thread() {
    @Override
    public void run() {
        while(true){
            if(pinPushButton.getValue() == 1) {
                sttG = 1 - sttG;
                sttR = 1 - sttR;
                sttB = 1 - sttB;
                pinR.setValue(sttR);
                pinG.setValue(sttG);
                pinB.setValue(sttB);
            }
            Vm.sleep(100);
        } 
    }
}.start();
Step 9: run RunHelloWorldApplication.java again and watch the results! 
View fully code here 
How to deploy
Step 1: open VS Code console  (CTRL + Shift + P) and select TotalCross: Deploy
Step 2: a second dialog box will appear and just fill in the board's information:
Step 3: see the results in screen or VNC
After basics
This was the beginning of application development for TotalCross embedded systems, how about taking a look at TCSample and seeing all that can be done? See dashboard made especially for Web Summit 2019:
See more
Are you interested in development with embedded systems? Contact us via Telegram! 
Bruno Muniz, Lucas Galvanini e Pedro Lyra no WebSummit
References
​Fritzing ​

Using Development certificate to test your apps

Running C++ applications with TotalCross

Last modified 2yr ago

Copy link

On this page

Introduction

Requirements

Guide

Discover VS Code plugin

Getting your Hello World App even more Cooler

How to deploy

After basics

References

Introduction

Requirements

Guide

Discover VS Code plugin

Getting your Hello World App even more Cooler 🥶 😅

How to deploy

After basics

See more

References