pyclickplc

Talk to AutomationDirect CLICK PLCs from Python. Async Modbus TCP client and server, the CLICK address model, and nickname CSV and DataView CDV file I/O.

It's the wire under pyrung and ClickNick, and it stands on its own as a Modbus client for any CLICK.

• Documentation: https://pyrung.com/pyclickplc/
• LLM docs index: https://pyrung.com/pyclickplc/llms.txt
• LLM full context: https://pyrung.com/pyclickplc/llms-full.txt

Install

uv add pyclickplc
# or
pip install pyclickplc

Requires Python 3.11+.

Quick example

import asyncio
from pyclickplc import ClickClient

async def main():
    async with ClickClient("192.168.1.10", 502) as plc:
        # Read and write registers with native Python types
        await plc.ds.write(1, 100)
        ds1 = await plc.ds[1]          # int
        await plc.y.write(1, True)     # bool
        df1 = await plc.addr.read("DF1")  # float

asyncio.run(main())

The quickstart uses ClickServer to simulate a PLC locally, so you don't need hardware to try it.

What's included

Modbus client — ClickClient reads and writes PLC values as native Python types (bool, int, float, str). Access by bank (plc.ds), by address string (plc.addr), or by tag name (plc.tag).

Modbus service — ModbusService wraps the async client for sync and UI applications with background polling and auto-reconnect.

Modbus server — ClickServer simulates a CLICK PLC over Modbus TCP. Use it for development and testing without hardware.

File I/O — Read and write CLICK nickname CSV and DataView CDV files. Compatible with CLICK programming software and ClickNick.

Learn more

Development

uv sync --all-extras --dev    # Install dependencies
make test                     # Run tests (uv run pytest)
make lint                     # Lint (codespell, ruff, ty)
make docs-build               # Build docs (mkdocs + mkdocstrings)
make docs-serve               # Serve docs locally
make                          # All of the above