The ESP-Modbus release v2.0.2 (2025-02-30)

[alisitsyn]

[2.0.2] 2025-02-30

ESP-Modbus release v2.0.2

Overview

The current release of ESP-Modbus v2, corresponds to the version v2.0.2 and supports creation of several instances of modbus master and slave objects. The public API interface is changed from beta version to allow creation of multiple communication objects with its own communication parameters, and the constructor API upon creation returns the handle to the interface structure that must be used as a first parameter for each API call for this particular object. For more information about the interface API and related changes see the official documentation for this release, described below. The goal of this beta release is to introduce new features and changes to the end users and get their feedback. The appropriate information or feature requests can be shared over on discussion page of the project. This is a release which is used as a start point for esp-modbus v2. This version will be used as latest official version and will include all official updates, back-ports from esp-modbus v1 and feature requests. It is recommended to use this version for your project because the esp-modbus v1 is obsolete and will not contain critical updates and new features.

The important references for this version:

• The previous version v2.0.1
• The integration branch for the releases of v2
• Discussions for version v2
• Issues for v2
• The release esp-modbus component version: 2.0.2

Documentation

The documentation for this version of the component can be found on the link below:

• ESP-Modbus documentation v2.0.2 (English)

Note

Documentation for ESP-MODBUS is available in two versions:

• Version v1.x.x: Refer to the ESP-MODBUS stable documentation v1
• Version v2.x.x: Access the ESP-MODBUS stable documentation v2

    flowchart LR
    Start["ESP-MODBUS Documentation"] --> Version{"Select Version"}
    
    Version -->|"v1.x.x"| Doc1["Stable Documentation v1"]
    Version -->|"v2.x.x"| Doc2["Stable Documentation v2"]
    
    Doc1 --> Updates["Project Discussion Page<br/><i>Latest Information</i>"]
    Doc2 --> Updates
    
    style Start fill:#f9f,stroke:#333,color:#000
    style Version fill:#bbf,stroke:#333,color:#000
    style Doc1 fill:#dfd,stroke:#333,color:#000
    style Doc2 fill:#dfd,stroke:#333,color:#000
    style Updates fill:#ffd,stroke:#333,color:#000

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Application Examples

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

• Modbus serial slave example

• Modbus serial master example

• Modbus TCP master example

• Modbus TCP slave example

Important Features And Changes

• The stack supports creation of multiple instances of master and slave with individual communication options and extended list of parameters;
• Master uses new extended format of slave connection table with the format: UID;IP address or host name;PORT;
  Examples: 12:2001:0db8:85a3:0000:0000:8a2e:0370:7334:502 - Defines the slave with defined IPV6, UID=12, PORT = 502,
  01:mb_slave_tcp_01:1502 - The slave with host name mb_slave_tcp_01, with UID=01 and PORT = 1502.
• The Modbus Master TCP controls the states of each slave individually and is able to renew connection/resolving phase if the slave connection is lost while it keeps polling cycle to remaining slaves.
• The Master is able to send request to the slave with any UID using specific API functions following with prefix _with;
• Support of Modbus TCP Master and Modbus TCP Slave multi-instance communication through the common driver;
• The release esp-modbus component version 2.0.2 can be selected for your project using the manifest file located in main folder of your project like below:
  idf_component.yml:

  dependencies:
    idf:
       version: ">=5.0"
    espressif/esp-modbus:
      version: "^2.0.0" # this line selects the latest v2 component release
    espressif/mdns:
      version: "^1.0.0"
    mb_example_common:
      path: "../mb_example_common" # the path to shared register structures
    protocol_examples_common: # the common component for connection management
      path: ${IDF_PATH}/examples/common_components/protocol_examples_common 

Plans && Status

Refer to previous release v2.0.1 for more information about v2.

• feature add custom fc handlers for master and slave v2 (IDFGH-10913, IDFGH-13746, IDFGH-6561) [Status: Testing]
  Any comments will be appreciated.

Related Issues

Added

• add slave report id command for master and slave (backport v2) (IDFGH-13856)

Fixed

• fix the mb_master unexpected event messages(timeout) severity to debug (IDFGH-14408)
• fix slave tcp stop method initialization (IDFGH-14743)
• esp-event event handler unregister function causes memory leak
• fix stack cpp compilation issues (IDFGH-14554)
• fix modbus handling of disabled comm modes (IDFGH-13866)
• modbus fix read input registers max number (backport v2)

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This discussion was created from the release Release [2.0.2] 2025-02-30.