> For the complete documentation index, see [llms.txt](https://docs.intrepidcs.com/vspy-3-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.intrepidcs.com/vspy-3-documentation/3.9.15/vehicle-spy-tutorials/tutorial-c-code-interface.md).

# Tutorial: C Code Interface

### Overview

This application note describes the basics of using the C Code Interface for Vehicle Spy. To use the C Code Interface, an install of Visual C++ Express or better, version 2005 or better is required. The Express Edition can be acquired from [Microsoft's website](https://www.microsoft.com/en-in/) for free. This tutorial does require some knowledge of C programming and familiarity with Visual Studio. In this example Visual C++ Express 2008 will be used.

### Parts of Vehicle Spy used

[C Code Interface](/vspy-3-documentation/3.9.15/vehicle-spy-main-menus/main-menu-scripting-and-automation/c-code-interface.md)\
Message Editor\
Application signals

### Hardware needed:

**neoVI FIRE 2, ValueCAN 4 family, RAD-Gigastar, RAD-Mars etc.** Please note that this feature is currently not supported on **neoVI FIRE 3** and **neoVI RED2**; however, a future update will include support for these devices.


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