Modbus RTU Slave library for Raspberry Pi Pico (RP2040) based on the C++ SDK

This repository contain working example Modbus RTU Slave implementation for rp2040 (Raspberry Pi Pico) with C++ SDK

Features:

• Modbus RTU Slave
• RS-485 support
• C++ style class
• Registers layout
• Separate setup read-only and read-write registers
• UART 0 and 1 support
• it works out of box and tested

How to use the example:

• Tune VS Code for Raspberry Pico development (instruction)
• You can use 2nd Raspberry Pico as a bootloader and debuger (instruction)
• Modify launch.json and setting.json files in .vscode according to your environment
• Start the debugging session
• Use Modbus Master emulator for connection (ModBus Poll for example)
• Change UART parameters in main.cpp and registers layout in modbus.cpp for your purpose
• Change stored data inside Modbus Manager class
• Change Switch-case optins according to your data and registers in mb_read_holding_register() and mb_write_single_register()

TODO:

• incapsulation for class data
• register layout definition throw init
• register checking throw std::dict instead of switch-case
• move on_mb_rx() to class logic
• mb_write_multiple_registers()
• mb_read_input_registers()