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3-Space Application Programming Interface

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The YEI 3-Space Application Programming Interface (API) is a series of functions, classes, and structure definitions designed to make writing applications that utilize the YEI 3-Space family of sensors fast and easy to support. Binary libraries (or source files depending on the supported language) are included for convenient integration into projects of any size or application.

Currently, the YEI 3-Space API supports C/C++ and Python natively. The Python variant of the API is provided as a main module source file with several support/utility source files. The C variant of the API is distributed as a header (.h) and dynamic link library (.dll + .lib). With the C API, users that require easy integration of the 3-Space family of sensors into programming environments not natively supported may import the dynamic link library and call its contained functions from the importing program, as the API's function prototypes are all compiled as C prototypes and are name mangled as such.

Key Features

  • Supports all members of the YEI 3-Space Sensor family
  • Provides access to all supported commands available to the 3-Space family of hardware in a human readable way
  • Designed to support all 3-Space hardware across all firmware versions, making application forward compatibility easy
  • Native support for Python (2.5x and 3.x) and C/C++
  • Support for any language that can import Microsoft Windows Dynamic Link Libraries (.dll)
  • Open source and free, allowing users to try and modify the API without consequence

System Requirements


Operating System - Windows XP(32-Bit), Windows Vista/7(32-Bit or 64-Bit)

3-Space Firmware Version - Firmware dated 11 Jan 2012 is the oldest recommended firmware.
NOTE: Due to changes being made to the gyroscope calibration pipeline, the "setGyroCalibrationParam" and "getGyroCalibrationParam" functions are not currently supported.

Dependencies - Python

PySerial 2.6 or newer


The YEI 3-Space APIs are released under the YEI 3-Space Open Source License, which allows for both non-commercial use and commercial use with certain restrictions.

For Non-Commercial Use, your use of Covered Works is governed by the GNU GPL v.3, subject to the YEI 3-Space Open Source Licensing Overview and Definitions.

For Commercial Use, a YEI Commercial/Redistribution License is required, pursuant to the YEI 3-Space Open Source Licensing Overview and Definitions. Commercial Use, for the purposes of this License, means the use, reproduction and/or Distribution, either directly or indirectly, of the Covered Works or any portion thereof, or a Compilation, Improvement, or Modification, for Pecuniary Gain. A YEI Commercial/Redistribution License may or may not require payment, depending upon the intended use.

Full details of the YEI 3-Space Open Source License can be found here

Downloads and Documentation


Legacy For firmware 1.0+

3-Space Python API Quick Start Guide, 1.0.0, updated 12 Apr 2012

3-Space Python API Documentation Reference (PDF), 1.1.0, updated 14 May 2012

3-Space C API Quick Start Guide, 1.1.0, updated 13 Jul 2012

3-Space C API Documentation Reference (PDF), 1.1.3, updated 13 Jun 2012

Python API

3-Space Python API Installer,, updated 19 Jun 2014

3-Space Python API Source,, updated 19 Jun 2014

Legacy Hosted on SourceForge (For firmware 1.0+)

Project Main Page




3-Space C API,, updated 06 Mar 2014

3-Space C API Source,, updated 06 Mar 2014

Legacy Hosted on SourceForge (For firmware 1.0+)

Project Main Page



API Examples

YEI 3-Space Python API Examples

YEI 3-Space C API Examples

Informational Resources


3-Space Python API Forum

3-Space C API Forum


http://www.python.org - Main site for the Python programming language.

http://pyserial.sourceforge.net - Project page for the PySerial Python module.