ESP-Modbus
The Espressif ESP-Modbus Library (esp-modbus) supports Modbus communication in the networks based on RS485, Wi-Fi, and Ethernet interfaces.
The component esp-modbus v2 (v2.x.x)
is the current supported component version:
Hosted Documentation
The documentation can be found through the link below:
Discussions
Protocol References
For the detailed protocol specifications, see The Modbus Organization.