Limewire

This repository contains the ground support software for MASA's Limelight mission. There are two main components:

• Limewire: A driver that enables communication of telemetry and valve commands between the rocket and our database, Synnax.

• Hydrant: A web-based GUI that enables remote command and control of the flight hardware.

[!NOTE] Although the telemetry + valve driver is only one component of the ground software, the repository is called "Limewire" because Hydrant was developed at a later point in time. This leads to a couple (rather unfortunate) conventions:

• This README will mostly refer to Limewire, but you can mentally replace "Limewire" with "Limewire and Hydrant" most of the time.
• When "installing Limewire," you're actually installing both Limewire and Hydrant, so there's no need to install Hydrant separately.

Project Lead: Ryan Wei

Installation

If you want to use Limewire on the DAQ PC, follow the first set of instructions. If you want to contribute to Limewire, follow the second set of instructions.

DAQ PC Installation

Limewire is installed on the DAQ PC using uv because it installs Limewire in a virtual environment while globally exposing the limewire command-line entry point.

Start by checking if Limewire is installed on the DAQ PC.

limewire

If Limewire is already installed, you should see log messages start to appear in the terminal. If you see a "command not found" error, install Limewire using the following command.

uv tool install git+https://github.com/masa-umich/limewire.git

If Limewire is already installed and you'd like to upgrade to the latest version, run the following command.

uv tool upgrade limewire

Development Installation

1. Make sure you have Python 3.12 or greater installed.

2. Install uv, a project manager for Python. If you're on macOS, you can install uv with Homebrew using brew install uv.

3. Clone the repository and cd into the project directory.

   git clone https://github.com/masa-umich/limewire.git
   cd limewire

4. Install the project dependencies.

   uv sync
   uv pip install -e .

5. Install Ruff, a linter and code formatter for Python projects. If you use VS Code, you can install the VS Code Ruff Extension.

   All code submitted to this project should be formatted using Ruff before being merged into main. An easy way to do this is configure your editor to enable "Format on Save".

Running Limewire and Hydrant

During operations, Limewire and Hydrant should be run on the DAQ PC while connected to the real flight computer. Assuming Limewire is installed following the instructions above, run the following command in the DAQ PC terminal to run Limewire:

limewire

Important

If Synnax is not running when Limewire is started, it will crash right away. Make sure Synnax is running on the DAQ PC before starting Limewire.

To run Hydrant, use the following command:

hydrant

To see all the runtime options available, run either command with the -h/--help flag.

Running development code on the DAQ PC

If you're working on Limewire or Hydrant in a development branch, you can uninstall the mainline version and install Limewire from your development branch.

uv tool uninstall limewire
uv tool install git+https://github.com/masa-umich/limewire.git@your-branch-name

After pointing the Limewire installation to the development branch, if you add new commits to your branch, you can easily upgrade Limewire using the following:

uv tool upgrade limewire

If you install a development version of Limewire, you MUST restore the mainline version of Limewire after you're done.

uv tool uninstall limewire
uv tool install git+https://github.com/masa-umich/limewire.git

Using FC Simulator

To make development easier, this repository contains a flight computer simulator, fc_simulator, that can be run locally for testing. There are two typical configurations that are used when running FC Simulator.

1. Limewire, Synnax, and FC Simulator running on your local machine.
2. Limewire and Synnax running on the DAQ PC and FC Simulator running on your local machine.

To run the FC simulator, follow the Limewire development installation instructions to install the simulator on your local machine. Then, open a new terminal, and activate the virtual environment for your project:

# Linux/macOS (bash/zsh)
source .venv/bin/activate

# Windows (CMD)
.venv\Scripts\activate.bat

# Windows (PowerShell)
.venv\Scripts\Activate.ps1

Next, start FC Simulator using the following command. (Note: Using 0.0.0.0 ensures that the FC simulator serves across all network interfaces.)

fc_simulator 0.0.0.0:8888

You might receive a pop-up asking if you want to allow Python to accept incoming network connections. Make sure this option is enabled.

Finally, start Limewire and connect to FC Simulator.

limewire [ip-address]:8888

Some caveats:

• If running Limewire locally:

  • You'll need open a new terminal to run Limewire, make sure you re-activate the virtual environment in this terminal.
  • The IP address field should be 127.0.0.1.

• If running Limewire on the DAQ PC:

  • Your local machine should be connected to the DAQ PC via Ethernet. Make sure and that your local IP is configured to be in the same subnet as the DAQ PC (here's how to change your local IP on macOS and Windows). Contact Ryan Wei or Felix Foreman-Braunschweig for the DAQ PC local IP address or if you run into any issues with this process.
  • The IP address field should be whatever IP address you configured your local machine to be.

Project Structure

This repository currently contains four packages in the src directory:

• limewire: The code for Limewire, which interfaces with the flight computer via TCP for valve commands and UDP for telemetry.
• fc_simulator: The Flight Computer Simulator, a TCP server that acts as a stand-in for the Flight Computer and enables local testing for Limewire.
• lmp: A shared library that implements message serializing and deserializing for the Limelight Messaging Protocol.
• hydrant: A web-based GUI that enables remote command and control of the rocket hardware.