Firmware Setup

Device Rules (udev)

PlatformIO Devices

curl -fsSL https://raw.githubusercontent.com/platformio/platformio-core/develop/platformio/assets/system/99-platformio-udev.rules | sudo tee /etc/udev/rules.d/99-platformio-udev.rules
sudo service udev restart

Source: https://docs.platformio.org/en/latest/core/installation/udev-rules.html#platformio-udev-rules.

Specific Device Rules

Tip

Specific device rules allows to define a particular name for a certain device, allowing static naming when connection through serial port communication.

In particularly with LattePanda SBCs, this feature is even more important to separate clearly which device is one (depending on the restart of the SBC with an Arduino or other device already plugged into the LattePanda, the onboard ATMega32 may be either /dev/ttyACM0 or /dev/ttyACM1).

Source: https://roboticsknowledgebase.com/wiki/tools/udev-rules/.

1. Open Visual Studio Code
   • GNOME menu
   • Terminal ($ code | $ code . to open the VS Code in the current directory)

2. Open PlatformIO extension

   • PIO Home Devices
     • /dev/ttyACM0
       • Description: LattePanda Leonardo
       • Hardware: USB VID:PID=3343:803A LOCATION=1-5:1.0
     • /dev/ttyACM1
       • Description: ttyACM1
       • Hardware: USB VID:PID=2341:0042 SER=9593132393135171D1E2 LOCATION=1-2:1.0

   Tip

   Another way to check the previous information is directly through terminal commands:

   udevadm info -a -n /dev/ttyACM0
   udevadm info -a -n /dev/ttyACM1
   

3. Execute the following commands

   sudo touch /etc/udev/rules.d/99-usb-serial.rules
   sudo tee /etc/udev/rules.d/99-usb-serial.rules <<EOF
   # LattePanda Leonardo (ATMega32 onboard of the SBC)
   SUBSYSTEM=="tty", ATTRS{idVendor}=="3343", ATTRS{idProduct}=="803a", SYMLINK+="ttyLattePandaATMega"
   
   # Arduino Mega
   SUBSYSTEM=="tty", ATTRS{idVendor}=="2341", ATTRS{idProduct}=="0042", SYMLINK+="ttyArduinoMega"
   
   EOF
   

CoolTerm

Tip

CoolTerm is a more advanced serial monitor with an User Interface (UI), compared to the native serial monitor implementation of PlatformIO.

1. Download CoolTerm (available at https://freeware.the-meiers.org/)
2. Execute the following commands

   mkdir ~/dev/tools -p
   mv ~/Downloads/CoolTermLinux64Bit.zip ~/dev/tools/
   
   cd ~/dev/tools/
   unzip CoolTermLinux64Bit.zip
   

3. Open CoolTerm

   cd ~/
   ./dev/tools/CoolTermLinux64Bit/CoolTerm
   

4. Connection Options
   • Serial Port
     • Port: /dev/ttyACM1 (note that LattePanda SBCs comes with ATMega32)
     • Baudrate: 115200 (check in your code the serial port's baud rate)
     • Data bits: 8
     • Parity: None
     • Stop bits: 1

   • Receive

     • Enable Direct RX update of text display

     • Enable Add timestamps to received data

       Tip

       Enabling timestamps may be useful to check the cycle time period.

     • Set Type to Time + Milliseconds