A simple computer system built around the ATmega328P microcontroller.

It is designed to be easy to use and understand at a deep level. It was developed to support a very hands-on course on the foundations of computers and programming, and as such it covers the core concepts that are typically left out of classes on programming.

Within an elegant and powerful integrated development environment there are:

• A simple assembler for the AVR assembly language.
• A compiler that is extremely easy to understand and extend so you can learn how compilers work and even develop your own custom high-level language(s).
• A simple and powerful Forth-like firmware that implements a command-line interpreter for the ATmega328P in less than a kilobyte.
• There is also some experimental support for running a simulator interactively, but it is still very tentative and unfinished and so is not included in this release.

Currently the source code is hosted on GitHub where you can download it, report bugs, contribute to or just fork it (it's open source under the GPL, see the COPYING file in the source.)

In addition to reading the source you should read the Manual (online HTML version) (This is still in a very rough draft stage with missing sections still to be filled in but I'm actively improving it.)

If you have Python (and Tkinter) installed then the only dependencies are:

• MyHDL
• IntelHex http://www.bialix.com/intelhex/ http://pypi.python.org/pypi/IntelHex/1.4
• Dulwich https://www.samba.org/~jelmer/dulwich/ http://pypi.python.org/pypi/dulwich

It is recommended to use Pip and Virtualenv to set up the working environment. Start in the toplevel directory, set up a virtual environment, install MyHDL (for some reason it's not on PyPI at the time of this writing) and then use Pip to install the rest of the requirements automatically:

virtualenv virt-env
source ./virt-env/bin/activate
cd thirdparty
tar xzf myhdl-0.7.tar.gz
cd myhdl-0.7
python setup.py install
cd ..
rm -rf myhdl-0.7
cd ..
pip install -r requirements.text 

Then run with:

python -m pigeon --init

(Leave off the "--init" switch after the first time, it just initializes the "roost" directory and isn't needed except for the first time you run the program.)

The system will use a "roost" directory to store your saved history. The default directory is $HOME/.pigeon but you can choose another location with the "--roost" switch.

The Pigeon Firmware is written as a reStructuredText document and then converted into a source file for the Pigeon Assembler using a utility script. You don't have to do this yourself as a copy of the extracted assembly source file is already included as assembler/asm.py, but it's good to know how that file gets made in case you want to modify it yourself.

To generate the asm.py file from the pigeon_firmware.rst file use the rest2asm.py script in the assembler subdirectory:

cd assembler
./rest2asm.py ../docs/pigeon_firmware.rst > asm.py