Fanuc Focas Python Portable

Using Python with FANUC FOCAS (FANUC Open CNC API Specifications) allows you to collect real-time data, monitor machine status, and even send commands to CNC controllers. Since the official FOCAS libraries are written in C, Python implementation typically involves using to bridge the DLL files. 1. Prerequisites and Setup

Before writing code, ensure you have the necessary library files and physical connectivity. FOCAS Library Files : You need the official FANUC DLLs, typically fwlib32.dll (for 32-bit) or fwlib64.dll (for 64-bit). Controller Configuration

: The CNC must have the FOCAS/Ethernet option enabled. Note its IP Address Port Number (the default is often Python Environment

: Use a 32-bit or 64-bit Python installation that matches your DLL version to avoid architecture mismatch errors. 2. Implementation with

The general workflow involves loading the DLL, establishing a connection to get a "handle," and then calling specific functions using that handle. Step 1: Load the Library and Define Structures

You must define Python classes that mirror the C structures (like for status info) used by FOCAS. # Load the FOCAS DLL (ensure the path is correct) = ctypes.WinDLL( fwlib32.dll

# Define a basic structure for machine status (mirroring ODBST) (ctypes.Structure): = [ ( , ctypes.c_short * ), ( , ctypes.c_short), # Selected automatic mode , ctypes.c_short), # Running status , ctypes.c_short), # Motion status , ctypes.c_short), # M, S, T, B status , ctypes.c_short), # Emergency stop status , ctypes.c_short), # Alarm status , ctypes.c_short), # Edit status Use code with caution. Copied to clipboard Step 2: Establish a Connection cnc_all_clibhndl3 for Ethernet connections to obtain a handle. = ctypes.c_ushort() ip_address 192.168.1.100 # Connect and get handle

= focas.cnc_all_clibhndl3(ip_address.encode(), port, timeout, ctypes.byref(libh)) : print( Connected! Handle: libh.value : print( Connection failed with error code: Use code with caution. Copied to clipboard Step 3: Read Data Once connected, you can call functions like cnc_statinfo to get the machine's current state. = focas.cnc_statinfo(libh, ctypes.byref(status)) : print( Auto Mode: status.aut # e.g., 1 for MDI, 2 for MEM Run Status: status.run # e.g., 3 for started Use code with caution. Copied to clipboard 3. Common Error Codes fanuc focas python

When troubleshooting, pay attention to these frequent return codes: : Success. -15 (EW_NODLL) : DLL file not found in the path. -16 (EW_SOCKET) : Cannot connect to the specified IP or port. 1 (EW_FUNC) : The requested function is not supported by the CNC. 4. Advanced Resources GitHub Projects : Community-driven wrappers like DGN-Monitor can simplify the setup by providing pre-defined structures. Documentation

: Detailed function catalogues and parameter manuals are often available via Scribd's FOCAS Overview macro variables

While Fanuc does not provide official Python libraries for its

(Fanuc Open CNC API Specifications) library—which is natively written for C, C++, and C#—you can still bridge the gap using third-party wrappers or low-level interface techniques. Integration Methods for Python Third-Party Libraries (Recommended) : A popular open-source wrapper available on

that performs protocol analysis to interface with Fanuc CNC machines via Python. Underautomation Fanuc.py

: A specialized SDK that allows Python to communicate with Fanuc robots and CNCs for data exchange and remote control, supporting both real hardware and ROBOGUIDE simulations. Low-Level ctypes : For advanced users, you can use Python’s library to directly load the standard Fanuc FwLib32.dll (Windows) or

(Linux) files. This requires manually mapping the C-style data structures and function calls defined in the FOCAS documentation Edge Gateways : Some industrial software agents, like the MindConnect Software Agent Using Python with FANUC FOCAS (FANUC Open CNC

, act as a middle layer. They connect to the Fanuc FOCAS protocol and then provide data to Python-based applications via MQTT or REST APIs. MindSphere documentation Common Use Cases Data Collection

: Reading system variables, tool offsets, and alarms for OEE (Overall Equipment Effectiveness) monitoring. Status Monitoring

: Using Python to visualize machine states, such as checking if a controller is in "Automatic" or "Manual" mode. Diagnostics

: Building custom dashboards to track machine health over time without needing a full SCADA system. Configuration Requirements

To enable a Python script to talk to a Fanuc machine, the CNC must first be configured: Fanuc Focas protocol - MindSphere documentation 29 Mar 2025 —

FANUC FOCAS (Fanuc Open CNC API Specifications) is a powerful set of software libraries used to bridge the gap between FANUC CNC controllers and external PC-based applications. While the native library is written in C/C++, Python developers can interact with it using specialized wrappers to perform high-level data collection and machine monitoring. www.robustel.store Core Concepts of FANUC FOCAS What it is:

A manufacturer API that allows external programs to "ask" the CNC machine for data or send specific commands without needing extra hardware like sensors. Access Methods: It communicates over (the most common method) or (High-Speed Serial Bus). Call the C function directly: cnc_allclibhndl3 Quick Start

Designed for older CNCs and Windows versions up to Windows 7.

Supports modern CNCs and newer operating systems like Windows 10 and 11. Machine Metrics Python Integration with FOCAS Because FOCAS is primarily a set of C-based files (like fwlib32.dll

), Python integration typically requires a wrapper or a protocol-based approach. Machine Metrics pyfanuc (PyPI)

This is a free, open-source Python library that simplifies interaction with FANUC controllers. It allows you to: axis-related data (position, speed, load). Read user-defined macro variables Collect machine status and alarms. ctypes method: Advanced developers often use Python’s built-in library to call the FOCAS C-functions directly from the fwlib32.dll provided by FANUC. Basic Workflow for a Python Connection

To establish a connection via Python, the application generally follows this sequence: Connect Fanuc CNC Router via FOCAS: A Step-by-Step Guide

Call the C function directly: cnc_allclibhndl3

Quick Start with `fanuc-focas`

pip install fanuc-focas

Connect

cnc = Fanuc('192.168.1.100', 8193)

Define handle type

cnc_handle = ctypes.c_ushort

Basic Workflow

Connect to the CNC – Establish a session using the CNC's IP address and port (usually 8193 for FOCAS Ethernet).
Call FOCAS functions – Request specific data (e.g., current spindle speed, feed rate, part count).
Process the data – Store in a database, publish to MQTT, or trigger alerts.
Close the connection – Cleanly release the session.

Your First Connection: Hello CNC

Let’s write a Python script to connect to the CNC and read the operation status.

import ctypes
from ctypes import wintypes
import time