Version 2.5.3 is the last 2.x release with support to python2.7.x and is in maintenance mode.
Version 3.0.0dev4 is the current prerelease of 3.0.0 (Supports only Python >=3.8)
Remark: "Supports only" means that we only test with those versions, lower versions (e.g. 3.7) might work typically depending on the actual setup.
Important
Note 3.0.0 is a major release with a number of incompatible changes.
Pymodbus is a full Modbus protocol implementation using a synchronous or asynchronous core. The preferred mode for asynchronous communication is asyncio, however for the moment twisted and tornado are also supported (due to be removed or converted to a plugin in a later version).
Supported modbus communication modes: - tcp - rtu-over-tcp - udp - serial - tls
Pymodbus can be used without any third party dependencies (aside from pyserial) and is a very lightweight project.
Requires Python >= 3.7
The tests are run against Python 3.7, 3.8, 3.9 and 3.10.
- Full read/write protocol on discrete and register
- Most of the extended protocol (diagnostic/file/pipe/setting/information)
- TCP, RTU-OVER-TCP, UDP, TLS, Serial ASCII, Serial RTU, and Serial Binary
- asynchronous(powered by asyncio/twisted/tornado) and synchronous versions
- Payload builder/decoder utilities
- Pymodbus REPL for quick tests
- Customable framer to allow for custom implementations
- Can function as a fully implemented modbus server
- TCP, RTU-OVER-TCP, UDP, TLS, Serial ASCII, Serial RTU, and Serial Binary
- asynchronous(powered by twisted) and synchronous versions
- Full server control context (device information, counters, etc)
- A number of backing contexts (database, redis, sqlite, a slave device)
Although most system administrators will find little need for a Modbus server on any modern hardware, they may find the need to query devices on their network for status (PDU, PDR, UPS, etc). Since the library is written in python, it allows for easy scripting and/or integration into their existing solutions.
Continuing, most monitoring software needs to be stress tested against hundreds or even thousands of devices (why this was originally written), but getting access to that many is unwieldy at best.
The pymodbus server will allow a user to test as many devices as their base operating system will allow (allow in this case means how many Virtual IP addresses are allowed).
For more information please browse the project documentation:
http://riptideio.github.io/pymodbus/ or http://readthedocs.org/docs/pymodbus/en/latest/index.html
For those of you that just want to get started fast, here you go:
from pymodbus.client.sync import ModbusTcpClient client = ModbusTcpClient('127.0.0.1') client.write_coil(1, True) result = client.read_coils(1,1) print(result.bits[0]) client.close()
For more advanced examples, check out the Examples included in the repository. If you have created any utilities that meet a specific need, feel free to submit them so others can benefit.
examples ├── common. -> Common examples for clients and server (sync/async), Payload encoders and decoders. ├── contrib. -> Examples contributed by contributors. Serial Forwarder, Database contexts etc.
If you are looking for UI,checkout Modbus Simulator or Modbus Cli
Also, if you have questions, please ask them on the mailing list so that others can benefit from the results and so that I can trace them. I get a lot of email and sometimes these requests get lost in the noise: pymodbus google group or at gitter or github discussions
Important
Note For async clients, it is recommended to use `asyncio` as the async facilitator. If using tornado make sure the tornado version is `4.5.3`.Other versions of tornado can break the implementation
Pymodbus REPL comes with many handy features such as payload decoder to directly retrieve the values in desired format and supports all the diagnostic function codes directly .
For more info on REPL refer Pymodbus REPL
You can install using pip or easy install by issuing the following commands in a terminal window (make sure you have correct permissions or a virtualenv currently running):
easy_install -U pymodbus pip install -U pymodbus
Or to install a specific release:
pip install -U pymodbus==X.Y.Z easy_install -U pymodbus==X.Y.Z
To Install pymodbus with twisted support run:
pip install -U pymodbus[twisted]
To Install pymodbus with tornado support run:
pip install -U pymodbus[tornado]
To Install pymodbus REPL:
pip install -U pymodbus[repl]
Otherwise you can pull the trunk source and install from there:
git clone git://github.com/bashwork/pymodbus.git cd pymodbus
To get latest release (for now v2.5.3 with python 2.7 support):
git checkout master
To get bleeding edge:
git checkout dev
To get a specific version:
git checkout tags/vX.Y.Z -b vX.Y.Z
- Then::
- python setup.py install
Either method will install all the required dependencies (at their appropriate versions) for your current python distribution.
- The repository contains a number of important branches and tags.
- dev is where all development happens, this branch is not always stable.
- master is where are releases are kept.
- All releases are tagged with vX.Y.Z (e.g. v2.5.3)
- All prereleases are tagged with vX.Y.ZrcQ (e.g. v3.0.0.0rc1)
If a maintenance release of an old version is needed (e.g. v2.5.4), the release tag is used to create a branch with the same name, and maintenance development is merged here.
The maintenance team is very small with limited capacity and few modbus devices.
However, if you would like your device tested, we accept devices via mail or by IP address.
That said, the current work mainly involves polishing the library and solving issues:
- Get version 3.0.0 released
- Make PEP-8 compatible and pylint, flake8, black and mypy ready
- Fixing bugs/feature requests
- Architecture documentation
- Functional testing against any reference we can find
- The remaining edges of the protocol (that we think no one uses)
The current code base is compatible python >= 3.7. Use make to perform a range of activities
$ make Makefile for pymodbus Usage: make install install the package in a virtual environment make reset recreate the virtual environment make check check coding style (PEP-8, PEP-257) make test run the test suite, report coverage make tox run the tests on all Python versions make clean cleanup all temporary files
Just fork the repo and raise your PR against dev branch.
- Here are some of the items waiting to be done:
- https://github.com/riptideio/pymodbus/blob/3.0.0/doc/TODO
- Pymodbus is built on top of code developed from/by:
- Copyright (c) 2001-2005 S.W.A.C. GmbH, Germany.
- Copyright (c) 2001-2005 S.W.A.C. Bohemia s.r.o., Czech Republic.
- Hynek Petrak, https://github.com/HynekPetrak
- Twisted Matrix
Released under the BSD License