2. Introduction to Source files and the Building Process.

The Arduino core contains all the built-in functions source files.

Source File Categorisation

The files have been categorized in the following types:

1. General Source Files
2. Port-related Source Files
   • Digital Port Source File
   • Analog Port Source File
   • Other Port Related Files
3. Timers/Timing Source Files
4. Hardware Serial Source Files
5. Wiring-related Source Files
6. Others

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General Source Files

The General Source Files category encapsulates all the source file that is related with built-in functions required for general Arduino Language Programming and core functioning.

i). Arduino.h

We know that a .h file describes the structure of the library and declares all its variables and functions The Arduino.h files contain:

• The declaration of mostly used built-in functions of the Arduino Programming Language. Example: digitalRead(), pinMode(), etc.
• Macro functions for general functions, not limited to rand(), min(), etc.

ii). main.cpp

The main.cpp is very important as it describes the basic program structure:

int main(void)
{
	init();

	initVariant();

#if defined(USBCON)
	USBDevice.attach();
#endif
	
	setup();
    
	for (;;) {
		loop();
		if (serialEventRun) serialEventRun();
	}
        
	return 0;
}

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Port Related Source Files

The Port Related Source Files category encapsulates all the source file that is related with built-in functions required for general port functioning. For example: digitalRead(), pinMode(), etc. We categorize the files in two sub-categories:

1). Digital Port Source File

wiring_digital.c

2). Analog Port Source File

wiring_analog.c

3). Other Port Related Files

i). wiring_pulse.c

ii). wiring_shift.c

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Timers/Timing Source Files

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Hardware Serial Source Files

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Wiring-related Source Files

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Others

See Also