RS485/RS232

This section introduces how to use the RS485/RS232 interface functions on the Raspberry Pi, laying the foundation for subsequent project development.

Enable Interface Configuration

• Enable the RS485/RS232 interface (disabled by default)
• Open the config.txt file (choose the correct path based on your system version):

  sudo nano /boot/config.txt            # For some older system versions

  sudo nano /boot/firmware/config.txt   # For most newer system versions

• To use RS485/RS232, add the following lines (these correspond to the 4 communication interfaces):

  

  dtoverlay=uart2-pi5                   # Corresponds to CH0
  dtoverlay=uart3-pi5                   # Corresponds to CH1
  dtoverlay=uart4-pi5                   # Corresponds to CH2
  dtoverlay=uart0-pi5                   # Corresponds to CH3

• After modification, reboot the Raspberry Pi to enable normal program-driven operation of RS485/RS232

  sudo reboot

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