arduino-blink-c
===================================
Program Arduino using C.

Author  : Sagar Patel   
Mail    : sagarpatel.9556@gmail.com

Follow the steps.

(1) Install Arduino environment by typing following command in shell.   
        sudo apt-get update && sudo apt-get install arduino arduino-core

Once you have arduino, you can program your arduino with Arduino's default coding style inside Arduino IDE. But for programming it with pure C (ANSI), you need to install other tools.

(2) Install gcc-avr, binutils-avr, gbd-avr, avr-libc and avrdude using following command.   
        sudo apt-get install gcc-avr binutils-avr gdb-avr avr-libc avrdude

(3) When the installation finishes, open the file blink.c in any text editor.   
    - You can find _BV used for accessing PORTB, which is MACRO defined in the headers located at "/usr/lib/avr/include/avr/iom328p.h" and “/usr/lib/avr/include/avr/sfr_defs.h”.  
    - Delay function is defined in utils/delay.h.   
    - All other things are self explainable.    
  
(4) Now its time to compile source code into object file and convert that into executable file, which will be finally provided in HEX. 
- To compile this source file into object file, use the following command.
        avr-gcc -Os -DF_APU=16000000UL -mmcu=atmega328p -c -o blink.o blink.c
    
- Convert this object file into executable file using following command.
        avr-gcc -mmcu=atmega328p blink.o -o blink
        
- Generate HEX file using following command.
        avr-objcopy -O ihex -R .eeprom blink blink.hex
        
- Finally, dump this HEX file into Arduino connected at /dev/ttyACM0 port.
        sudo avrdude -F -V -c arduino -p ATMEGA328p -P /dev/ttyACM0 -b 115200 -U flash:w:blink.hex    

The shell script "code_upload.sh" contains all the commands from step 4. Use it like followed to do step 4 in single command.
        ./code_upload.sh  blink.c   /dev/ttyACM0  115200


The shell file format is followed.
        ./code_upload.sh  <program_path>  <port>  <baud_rate>

Use the datasheet of ATMega328p to explore more.
For any query send an email to author.