Protocols

ESP-TLS

Removed Deprecated API

The deprecated esp_tls_conn_http_new() function has been removed. Use either:

esp_tls_conn_http_new_sync() for blocking connections
esp_tls_conn_http_new_async() for non-blocking connections

The new API requires you to create the esp_tls_t structure using esp_tls_init() and provides better control over the connection process.

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:

ESP-Modbus component on GitHub

Documentation

Application Examples

Since ESP-IDF version v6.0, the examples for component esp-modbus v1 which is obsolete have been removed from ESP-IDF.

legacy esp-modbus v1.x.x examples (esp-idf v5.5)

The examples below demonstrate the ESP-Modbus library of serial and TCP ports for both slave and master implementations respectively.

mb_serial_slave - demonstrates how to use ESP32-S2 as a Modbus serial slave device with the esp-modbus stack, enabling an external Modbus host to read and write device parameters using the Modbus protocol.
mb_serial_master - demonstrates how to use the esp-modbus stack port on ESP32-S2 as a Modbus serial master device, capable of reading and writing values from slave devices in a Modbus segment.
mb_tcp_slave - demonstrates the esp-modbus TCP slave stack port, allowing an external Modbus host to read and write device parameters via the Modbus protocol.
mb_tcp_master - demonstrates how to use the esp-modbus stack port on ESP32-S2 as a Modbus TCP master device, capable of reading and writing values from slave devices in a Modbus network. <https://github.com/espressif/esp-modbus/tree/main/examples/tcp/mb_tcp_master>`__

Please refer to the README.md documents of each specific example for details.

Discussions

Discussions for version v2

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