current community

your communities

more stack exchange communities

company blog
Stack Exchange Inbox Reputation and Badges
tour help
Arduino Stack Exchange is a question and answer site for developers of open-source hardware and software that is compatible with Arduino. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top
up vote 7 down vote favorite
4

I have started to play with and arduino UNO quite recently (without any prior experience with micro-controllers). I would like to use emacs instead of the IDE, and I'd also like to know what the IDE does under the hood, in order to be able to write my own makefile. The tutorials I've found are either outdated, or are presented as a series of steps without any explanation. I'd appreciate it if someone could explain to me how the whole compliation/linking/upload process works using gcc-avr and avr-dude, and how it is used by the IDE.

share|improve this question
3  
You can take a look under the hood by "Show verbose output during: ☑ compilation ☑ upload" Under File → Preferences. – jippie Apr 27 '14 at 17:47
up vote 10 down vote accepted

If you want an exact duplication of what the IDE does but want it driven from the command line, that's what Ino is for. The full Arduino build process involves copying a lot of files from a lot of places, and is generally not trivial to duplicate.

If you're ready to let go of .ino files and the Arduino libraries, you get a much simpler toolset. avr-gcc compiles, avrdude uploads, and you're done. Here's one of my makefiles from a simple project:

CC=avr-gcc
CXX=avr-c++
CXXFLAGS=-Wall -Wextra -mmcu=atmega1284p -Os
CFLAGS=$(CXXFLAGS)
BINARY=ledmatrix
OBJECTS=

all: $(BINARY)
↹@avr-size $<

$(BINARY): $(OBJECTS)

clean:
↹@rm -f $(BINARY) $(BINARY).hex $(OBJECTS)

upload: $(BINARY).hex
↹@avrdude -c usbasp -p m1284p -U flash:w:$<:i

%.hex: %
↹@avr-objcopy -j .text -j .data -O ihex $< $@

.PHONY: all clean upload

If copying-and-pasting, be sure to replace all "↹" with tab characters.

EDIT:

I have created a repository with my buildsystem on Github.

share|improve this answer
    
Thanks, your makefile is pretty much what i was trying to come up with. But i guess getting rid of the libraries means that i wont be able to use functions such as digitalWrite()? In that case, where should i look to learn their plain C equivalents? – Ash Apr 27 '14 at 18:06
1  
The Arduino libraries would contain their equivalents, but they can be a bit erudite to read. I recommend finding a low-level AVR tutorial to work through that will explain to you the various registers and peripherals. Oh, and the datasheet. Always get the datasheet. – Ignacio Vazquez-Abrams Apr 27 '14 at 18:09

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.