(I) Robotis CM-900 C++ crash examples tutorial

This is the first example in a serie of cheap (absolutely free and cheap) articles to get some basic and practical C++ knowledge. It will references the great explanations provided at www.cplusplus.com C++ tutorial. And using the very cheap and opensource (about 20$/€) Robotis 32 bits microcontroller board CM-900 (STM32 based) and Arduino based IDE.

Here you can download the file with the code, and you can find links to a lot of free tutorials, courses and books to learn C++ here.


[sourcecode language="cpp"]
// C++ crash tutorial with Robotis CM-900.

// First example: http://softwaresouls.com/softwaresouls/2013/06/23/c-crash-tutorial-using-robotis-cm-900-board-and-ide-i/

/*
Hello World shows messages on construction and destruction
Also it lets you to salute.
Showing always its assigned identifiction number MyId
*/
class HelloWorld
{
private:
int myId; //Object identification num ber

public:

// class constructor http://www.cplusplus.com/doc/tutorial/classes/
HelloWorld(char *message, byte id)
{
myId=id;
SerialUSB.print(message);
printId();
}

// class destructor http://www.cplusplus.com/doc/tutorial/classes/
~HelloWorld()
{
SerialUSB.print ("Destructing object: ");
printId();
}

void printId()
{
SerialUSB.print(" ID:");
SerialUSB.println(myId);
SerialUSB.println(" ");
}

void Salute(char *name)
{
SerialUSB.print("Hi!, ");
SerialUSB.println(name);
SerialUSB.print("Regards from object: ");
printId();
}
};

/*
void setup() function it's only executed one time at the start of the execution.
It is called from a hidden main() function in the Ronbotis CM-900 IDE core.

\ROBOTIS-v0.9.9\hardware\robotis\cores\robotis\main.cpp
Note: "while (1)" is a forevr loop ( http://www.cplusplus.com/doc/tutorial/control ):

(Basic structure http://www.cplusplus.com/doc/tutorial/program_structure/)

int main(void) {
setup();

while (1) {
loop();
}
return 0;
}
*/
void setup()
{
SerialUSB.begin(); //initialize serial USB connection
delay(3000); //We will wait 3 seconds, let the user open (Control+Shift+M) the Monitor serial console
}

//We will not see neither the construction nor the destruction of this global object because serial port it's not still initiated
HelloWorld hw0("construction object", 0); //Object construction http://www.cplusplus.com/doc/tutorial/classes/

// A counter to see progress and launch events
int iterationCounter=0; //An integer variable to count iterations http://www.cplusplus.com/doc/tutorial/variables

// void loop() will be executing the sentences it contains while CM-900 is on.
void loop()
{
// Lets's show only the first 5 iterations http://www.cplusplus.com/doc/tutorial/control/
if (iterationCounter<5)
{
SerialUSB.print("starting iteration #");
SerialUSB.println(++iterationCounter); // firts, iterationCounter is incremented and then printed

// We will see the consttruction and destruction messages from this local (inside the loop function) object. Object construction http://www.cplusplus.com/doc/tutorial/classes/
HelloWorld hw1("constructing object", 1);
hw1.Salute("Joe");

if (iterationCounter==3)
{
// We will see the consttructiona and destruction messages from this local (inside the "if" block inside the "loop" function) object. Objet construction http://www.cplusplus.com/doc/tutorial/classes/
HelloWorld hw2("constructing object", 2);
hw2.Salute("Jones");
} // Objet hw2 destruction http://www.cplusplus.com/doc/tutorial/classes/

//Let's show that object hw0 is alive
hw0.Salute("Pepe");

SerialUSB.print("ending iteration #");
SerialUSB.println(iterationCounter++); // first cpunter is printed, then incremented.
} // Objet hw1 destruction http://www.cplusplus.com/doc/tutorial/classes/
} // Program end. Objet hw0 destruction http://www.cplusplus.com/doc/tutorial/classes/
[/sourcecode]