RS485

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

Enabling Interface Configuration

• Enable the RS485 interface (disabled by default)
• Edit the config.txt file

  sudo nano /boot/firmware/config.txt 

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

  # Corresponding to CH0
  dtoverlay=uart0-pi5      

  # Corresponding to CH1   
  dtoverlay=uart2-pi5      

  # Corresponding to CH2 
  dtoverlay=uart3-pi5      

  # Corresponding to CH3  
  dtoverlay=uart4-pi5                  

• Enable all 4 RS485 channels simultaneously

  # Enable CH0 ~ CH3 RS485 channels at the same time
  dtoverlay=uart0-pi5 
  dtoverlay=uart2-pi5 
  dtoverlay=uart3-pi5  
  dtoverlay=uart4-pi5 

• After modification, reboot the Raspberry Pi, then the program can drive RS485 normally

  sudo reboot

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