AVR Studio 7 and the Arduino Mega 2560

I've heard of the Arduino family of microcontroller boards but have not worked with one until today. I decided to take a closer look because I do know the Atmel AVR, in particular the 8-bit mega family, and an Arduino is a reasonably cheap way to get one to experiment with. I chose an Arduino Mega 2560 board.

My AVR experience is based on various editions of Atmel's Studio IDE - so I wanted to find out how to use it with the Arduino hardware, ignoring the Arduino software as much as possible.

Here are the steps I followed to run a simple C program. My starting point was a fresh install of Atmel Studio (version 7.0.783) and the Arduino software (version 1.6.7) on a desktop PC running Windows 10 - and (of course) an Arduino Mega 2560 connected to the PC via USB, with it's green power LED on.

(Note that you can click on an image to see a full size / full resolution version.)

• on the Start Page, select New Project...

  

  Atmel Studio 7 - Start Page

• in the New Project dialog, select GCC C Executable Project, specify a Name and a Location then click OK
  

  

  Atmel Studio 7 - New Project dialog

• in the Device Selection dialog, select ATmega2560 (the type of AVR microcontroller used on the Arduino board) then click OK
  

  

  Atmel Studio 7 - Device Selection dialog

• a minimal, template project is created, ready for you to enter code...
  

  

  Atmel Studio 7 - Virgin Project

• choose test Properties (assuming your project is called test) from the Project menu, then select Toolchain, and under AVR/GNU C Compiler select Symbols
  

  

  Atmel Studio 7 - Project Properties tab

• in the Defined Symbols (-D) box, click the Add Item button and enter F_CPU=16000000UL (this specifies the processor clock frequency in Hertz; for the Arduino Mega 2560 this is 16MHz - the "UL" suffix means Unsigned Long)
  

  

  Atmel Studio 7 - adding a defined symbol

• select the main.c tab and enter enough C code to see life signs - mine pulses the "L" LED once then twice, over and over
  

  

  Atmel Studio 7 - entering a simple C test program

       
#include <avr/io.h>
#include <util/delay.h>

int main(void)
{
 DDRB |= (1 << PORTB7); // PORTB7 direction = out
 
 while (1)
 {
  
  // 1 pulse
  PORTB |= (1 << PORTB7); // PORTB7 hi = LED L on
  _delay_ms(500); // 0.5 sec
  PORTB &= ~(1 << PORTB7); // PORTB7 hi = LED L off
  
  // delay
  _delay_ms(2000); // 2 sec

  // 2 pulses
  PORTB |= (1 << PORTB7);
  _delay_ms(500);
  PORTB &= ~(1 << PORTB7);
  _delay_ms(500);
  PORTB |= (1 << PORTB7);
  _delay_ms(500);
  PORTB &= ~(1 << PORTB7);

  // delay
  _delay_ms(2000);
 }
}

• now the interesting part - adding support for the Arduino's programming mechanism, which requires the use of the avrdude utility that is included in the Arduino software installation


• first, identify the COM port that the Arduino is connected to by running the Device Manger - in my case it was COM3...
  

  

  Device Manager (Windows 10) showing Arduino COM port

• choose External Tools... from the Tools menu
  

  

  Atmel Studio 7 - External Tools dialog (before)

• in the External Tools dialog...
• change the Title to Program
• enter the following in the Command box:
  

         
  c:\Program Files (x86)\Arduino\hardware\tools\avr\bin\avrdude.exe
  
  

• enter the following in the Arguments box, changing -P COM3 to match the COM port that the Arduino is connected to on your machine:
  

         
  -v -C"C:\Program Files (x86)\Arduino\hardware\tools\avr\etc\avrdude.conf" -p atmega2560 -c wiring -P COM3 -b 115200 -D -U flash:w:$(TargetDir)$(TargetName).hex:i
  
  

• check the Use Output window box
• click OK
  

  

  Atmel Studio 7 - External Tools dialog (after)

• there is now a Program option on the Tools menu which will flash the compiled code into the Arduino board - let's add a corresponding shortcut to the UI:
• select Add or Remove Buttons to the right of No Tool, then Customize...
  

  

  Atmel Studio 7 - adding a custom button

• the Customize dialog appears:
  

  

  Atmel Studio 7 - Customize dialog

• click Add Command...
• under Categories select Tools
• under Commands scroll down and select External Command 1
  

  

  Atmel Studio 7 - Add Command dialog

• click OK then Close the Customize dialog
• there is now a Program button left of the device (ATmega2560) button
• to build the code, choose Build Solution from the Build menu (or hit F7):
  

  

  Atmel Studio 7 - after build

• now program the board by clicking the Program button - this will produce some rapid progress messages from the avrdude programming utility in the Output pane:
  

  

  Atmel Studio 7 - after programming

• voila - you should see the "L" LED blinking once then twice, repeatedly