PeaPod OS

Main software for PeaPod.

A cloud-connected isolated and automated plant growth environment, able to generate any environment from a combination of independent environment parameters.

Designed as both a hassle-free food production system and a research tool for precise and distributed mapping of the plant-environment relationship.

Table of Contents

• Background
• Production
  • Setting Up Raspberry Pi
• Development
  • Arduino Test Suite
  • Raspberry Pi Serial Testing
  • Build from Source

Background

Production

Setting Up Raspberry Pi

The following are performed on a computer:

1. Format a microSD card (>=4GB) with a single FAT partition.
2. Download the Raspberry Pi Imager (Download).
3. Flash the SD card with a Raspberry Pi OS Lite image.

Note: In Future, a custom PeaPod Raspberry Pi OS Lite image will be released with steps 5, 6, and 12 already complete.

4. Plug in a keyboard and display, insert the microSD card, and power the Raspberry Pi device.

The following are performed on the Raspberry Pi, with a keyboard and monitor:

5. Login with the default username (pi) and password (raspberry).
6. Execute sudo raspi-config and perform these steps to setup the Pi:
   1. System Options > Wireless Lan - Setup WiFi and connect to the Internet
   2. System Options > Hostname - Set a unique host name (e.g. john-peapod)
   3. System Options > Boot/Auto Login - Select Console Autologin
   4. Interface Options > SSH - Enable SSH Server
   5. Interface Options > Serial Port - Disable serial login shell, but Enable the serial port hardware
   6. Performance Options > GPU Memory - 256 (MB)
   7. Localisation Options > Locale (i.e. en_US.UTF-8)
   8. Localisation Options > Timezone (i.e. US > Eastern)
   9. Localisation Options > Keyboard (i.e. Generic 105-key > English (US) > Default > No compose key)
   10. Optional: Advanced Options > Expand Filesystem
   11. Reboot to save: sudo reboot

You can now SSH into the Raspberry Pi to perform the rest of the setup (ssh [email protected], or with VS Code)

Note: In Future, steps 7-11 will be performed at runtime.

7. Update Packages:
   1. Update package listings, upgrade existing packages: sudo apt-get update && sudo apt-get upgrade -y
   2. Install Node.JS, the Node package manager, and avrdude: sudo apt-get install -y nodejs npm avrdude python3-venv (could take a while)
   3. Install main software package: sudo npm i -g @peapodtech/peapodos --save

8. Install PlatformIO Core with python3 -c "$(curl -fsSL https://raw.githubusercontent.com/platformio/platformio/master/scripts/get-platformio.py)"

9. Create a custom configuration file for the AVR flash utility avrdude to be able to program the Arduino Nano via ICSP over the Raspberry Pi's GPIO pins:

   1. Create a local copy of the avrdude configuration file with cp /etc/avrdude.conf ~/software/microcontroller/avrdude_gpio.conf, then modify your copy with nano ~/software/microcontroller/avrdude_gpio.conf. Copy the following to the end of the file:

      # Raspberry Pi GPIO configuration for avrdude.
      programmer
        id    = "peapod";
        desc  = "Use the Linux sysfs interface to bitbang GPIO lines";
        type  = "linuxgpio";
        reset = 5;
        sck   = 6;
        mosi  = 12;
        miso  = 13;
      ;

      (Ctrl-O to save, Ctrl-X to exit)

   2. Verify the configuration and connection to the Arduino with sudo avrdude -p m328p -C/avrdude_gpio.conf -c peapod -v. A successful output should look something like:

      avrdude: Version 6.3-20171130
           Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
           Copyright (c) 2007-2014 Joerg Wunsch
      
           System wide configuration file is "/home/pi/avrdude_gpio.conf"
           User configuration file is "/root/.avrduderc"
           User configuration file does not exist or is not a regular file, skipping
      
           Using Port                    : unknown
           Using Programmer              : peapod
           AVR Part                      : ATmega328P
           Chip Erase delay              : 9000 us
           PAGEL                         : PD7
           BS2                           : PC2
           RESET disposition             : dedicated
           RETRY pulse                   : SCK
           serial program mode           : yes
           parallel program mode         : yes
           Timeout                       : 200
           StabDelay                     : 100
           CmdexeDelay                   : 25
           SyncLoops                     : 32
           ByteDelay                     : 0
           PollIndex                     : 3
           PollValue                     : 0x53
           Memory Detail                 :
      
                                    Block Poll               Page                       Polled
             Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
             ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
             eeprom        65    20     4    0 no       1024    4      0  3600  3600 0xff 0xff
             flash         65     6   128    0 yes     32768  128    256  4500  4500 0xff 0xff
             lfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
             hfuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
             efuse          0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
             lock           0     0     0    0 no          1    0      0  4500  4500 0x00 0x00
             calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00
             signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00
      
           Programmer Type : linuxgpio
           Description     : Use the Linux sysfs interface to bitbang GPIO lines
           Pin assignment  : /sys/class/gpio/gpio{n}
             RESET   =  8
             SCK     =  11
             MOSI    =  10
             MISO    =  9
      
      avrdude: AVR device initialized and ready to accept instructions
      
      Reading | ################################################## | 100% 0.00s
      
      avrdude: Device signature = 0x1e950f (probably m328p)
      avrdude: safemode: lfuse reads as FF
      avrdude: safemode: hfuse reads as DA
      avrdude: safemode: efuse reads as FD
      
      avrdude: safemode: lfuse reads as FF
      avrdude: safemode: hfuse reads as DA
      avrdude: safemode: efuse reads as FD
      avrdude: safemode: Fuses OK (E:FD, H:DA, L:FF)
      
      avrdude done.  Thank you.

10. Perform first-time flashing with ~/.platformio/penv/bin/platformio run -d ~/software/microcontroller/ --target upload

11. Edit the sudoers file to allow avrdude to be executed using sudo without a password:

    1. Open the sudoers file: sudo visudo

    2. Add the following line to the end (assuming your username is pi, the hostname is peapod, and the avrdude binary is located at /usr/bin/avrdude):

       pi peapod = (root) NOPASSWD: /usr/bin/avrdude

       (Ctrl-O to save, Ctrl-X to exit; avrdude can be located with whereis avrdude)

12. Install the UV4L camera library:

    1. curl https://www.linux-projects.org/listing/uv4l_repo/lpkey.asc | sudo apt-key add -
    2. Add the package listings: echo "deb https://www.linux-projects.org/listing/uv4l_repo/raspbian/stretch stretch main" | sudo tee /etc/apt/sources.list.d/uv4l.list
    3. Update packages: sudo apt-get update
    4. Install the core library, the Raspberry Pi driver, extra scripts, adn WebRTC support: sudo apt-get install uv4l uv4l-raspicam uv4l-raspicam-extras uv4l-webrtc-armv6

13. Populate a .env file with Firebase and Google and/or GitHub auth keys (a template is provided as .env.template), as well as the field SERIALPORT="/dev/ttyS0" (Raspberry Pi Zero 2 W GPIO mini-UART).

14. Run the main program by executing peapodos.

Development

Arduino Test Suite

To run the PlatformIO Arduino test suite: ~/.platformio/penv/bin/platformio test -d ~/software/microcontroller/

Raspberry Pi Serial Testing

To test the GPIO serial port (/dev/ttyS0), connect GPIO pins 8 and 10 (TX and RX) and execute the following:

1. Install the Python package manager pip: sudo apt-get install pip
2. Install the Serial package pyserial: pip install pyserial
3. Execute the test script: python ~/PeaPod/software/tests/serialTest.py

Correct output should look like:

Serial port '/dev/ttyS0' ready for test:
Sent 20 bytes: 'Testing Raspberry Pi GPIO serial port ...'
Received 20 bytes: 'Testing Raspberry Pi GPIO serial port ...'
Port '/dev/ttyS0' is is setup correctly!

Build from Source

1. Install TypeScript language support and compiler, as well as a Node build tool: sudo npm install -g typescript
2. Clone source
3. Navigate to software/ folder
4. Build the serialport package from source: sudo npm install serialport --unsafe-perm --build-from-source
5. Install all other Node dependencies: npm i
6. Compile the source with tsc and execute with node .