Using git for Arduino programs

Overview

Teaching: 20 min
Exercises: 10 min

Questions

• How can I maintain Arduino programs with git?

• How can I create a github reposistory from the command line?

Objectives

• Use git for version control with Arduino sketches.

You should consider using version control for any serious programming you do. Here is a quick set up steps to help you create a repo and maintain a repository with an Arduino program.

You should have an account at github, an ssh key, and have git configured on your raspberry pi. If you’ve gone through the Software Carpentry Version Control with Git you should have already set up most of these.

You can check your ssh keys by listing the contents of your .ssh directory

$ ls -al ~/.ssh

If you don’t have an id_rsa.pub file listed, you can create one:

$ ssh-keygen

Follow along with the prompts and leave the password blank.

To configure github to use your public key, you can list out the key:

$ cat ~/.ssh/id_rsa.pub

Then select and copy the contents of the key, visit your GitHub settings page, click New SSH key, and past the key into the field. (You also have to give the key a title – you can use the hostname of your pi.)

Finally, test the configuration:

$ ssh -T git@github.com

You can check your git configuration with git config:

$ git config -l

If your user.email and user.name are not set, you can set them:

$ git config --global user.email "you@example.com"
$ git config --global user.name "Your Name"
$ git config --global init.defaultBranch main

If you haven’t installed hub, you need that first.

$ sudo apt-get install hub

Create a directory Once the repository exists you can push changes to the repository online. Here are a series of commands that assume you have an ssh key set up with github.

$ mkdir projectname
$ cd projectname
$ touch README.md
$ git init
$ git add *
$ git commit -m "First commit."

With hub you can interact with github and easily create a new repository:

$ hub create

Or you should be be able to. Unfortunately, you currently may need to create a “personal access token” for hub via Settings -> Developer Settings -> Personal Access Tokens. Once you create a token, you can copy it and then paste it in where you get asked for a password.

You should now be able to push your changes to github.

$ git remote add origin git@github.com:USERNAME/projectname.git
$ git push -u origin main

For some Arduino programs, you may need to “add” other files, but avoid including the compiled files (.elf and .hex). Create a “.gitignore” file (e.g. “nano .gitignore”) an insert these patterns to avoid adding them by mistake.

*.elf
*.hex

Then you can use the following commands to push changes to your github repository.

$ git add *
$ git commit -m "informative message"
$ git push

Key Points

• Maintain all your programming in version control.