Fanuc Focas Documentation Upd Jun 2026

FOCAS is an application programming interface (API) that allows external programs to access the internal data of a FANUC CNC. It operates on a client-server model, where the external computer (client) sends requests to the CNC (server) via Ethernet.

The documentation specifies how strings (like program names or messages) are handled. Older FANUC systems use a specific format for characters that often requires conversion. The documentation details whether a function expects ASCII or FANUC’s internal character coding, which is critical when writing strings to the CNC screen or program directories. fanuc focas documentation

The most direct form of documentation for a C/C++ programmer is the FOCAS header file (commonly fwlib32.h or fwlib64.h ). This file defines the function prototypes, data structures, and constant values required to compile a project. It is the primary source of truth for function signatures. FOCAS is an application programming interface (API) that

FOCAS is FANUC’s official library (DLLs/API) for reading/writing data from FANUC CNCs (Series 0i, 30i, 31i, 35i, etc.) over Ethernet or HSSB. Older FANUC systems use a specific format for

// 2. Read macro variable #100 ODBMACRO macro; cnc_rdmacro(h, 100, 0, ¯o); // macro.data = value

The FOCAS documentation is not a single user manual; it is a technical reference library. Navigating it effectively requires understanding its primary components.

To start working with FANUC FOCAS (Factory Automation Computer Aided Engineering Support), you need to understand it as a set of library files (DLLs) that acts as a translator between a computer application and a FANUC CNC controller.