Subsystems

A bridge between the UDP network and the CAN bus

Raspberry Pi setup

Here is a comprehensive list of how to set up this Pi from a clean image

1. Connect to WiFi:

• SSID: mydevicesbing, no password
• Disable MAC randomization:

  printf "[connection]\nwifi.mac-address-randomization=1\n\n[device]\nwifi.scan-rand-mac-address=no\n" | sudo tee /etc/NetworkManager/conf.d/100-disable-wifi-mac-randomization.conf

• Register this device's MAC address at mydevices.binghamton.edu
• Reboot and verify that WiFi has internet

2. Setup the Subsystems repository:

• Clone the repository:

  git clone https://github.com/BinghamtonRover/Subsystems rover/subsystems
  git switch -c pi

• On your PC, set up this Pi as a Git remote:

  cd path/to/your/subsystems
  git remote add pi [email protected]:~/rover/subsystems
  git fetch
  cd network
  git remote add pi [email protected]:~/rover/subsystems/network
  git fetch

3. Configure CAN

• Add the following to the end of /boot/config.txt

  [all]
  enable_uart=1
  
  # STORE-BOUGHT CAN HAT
  # dtparam=spi=on
  # dtoverlay=mcp2515-can0,oscillator=12000000,interrupt=25,spimaxfrequency=2000000
  
  # 10/22/2022 PI HAT
  dtparam=spi=on
  dtoverlay=mcp2510-can0,oscillator=16000000,interrupt=12

4. Install dependencies:

• Install Python libraries:

  cd rover/subsystems
  pip3 install -r requirements.txt
  sudo pip3 install -r requirements.txt

  These commands will take a while. The sudo variant is needed to run the subsystems program as root
• Install OpenCV, needed for the video program

  sudo apt-get update
  sudo apt-get install build-essential cmake pkg-config libjpeg-dev libtiff5-dev libjasper-dev libpng-dev libavcodec-dev libavformat-dev libswscale-dev libv4l-dev libxvidcore-dev libx264-dev libfontconfig1-dev libcairo2-dev libgdk-pixbuf2.0-dev libpango1.0-dev libgtk2.0-dev libgtk-3-dev libatlas-base-dev gfortran libhdf5-dev libhdf5-serial-dev libhdf5-103 python3-pyqt5 python3-dev -y

• Install can-utils:

  sudo apt-get install can-utils

  Now you can use candump and cansend

5. Convenience scripts

• Setup a script to start the subsystems program in ~/subsystems.sh:

  #!/bin/bash
  echo Starting subsystems...
  sleep 1
  sudo pigpiod
  sleep 1
  cd /home/pi/rover/subsystems
  python3 -m bin.main

• Setup a program to stop the subsystems program in ~/kill-subsystems.sh:

  #!/bin/bash
  sudo kill `pgrep -f "python3 -m bin.main"`

• Add the following service to a new file /etc/systemd/system/subsystems.service:

  [Unit]
  Description=Rover Subsystems
  After=network-online.target
  
  [Service]
  ExecStart=/home/pi/subsystems.sh
  ExecStop=/home/pi/kill-subsystems.sh
  TimeoutStopSec=5
  User=pi
  
  [Install]
  WantedBy=multi-user.target

• Test the service: Then run sudo systemctl enable subsystems.service

6. Setup the Pi's static IP address over Ethernet

• Right click on the network icon, configure the eth0 interface
• Set IP=192.168.1.20, router=192.168.1.2
• In Preferences > Raspberry Pi Configuration > Interfaces, enable SSH
• Verify that you can ssh into [email protected] over Ethernet