Introduction

An assortment of C utilities and hardware abstractions that work on multiple platforms including x86 PC\'s and microcontrollers. One day this library could be more generically useful, but currently it is developed according to the needs of the omnid robot project.

Main Features

1. Works on x86 Linux and tiva microcontrollers
2. UART serial library with code to lower the default latency of FTDI USB to serial converters and to use RS-485 serial devices on linux.
   • Only some fixed baud rates are supported, but they are added on an as-needed basis
   • It is also possible to set the default FTDI latency with udev rules
3. Protocol and serialization/de-serialization code for use over the uart
4. Lock-free single-producer single-consumer queue
5. CMake utilities
   • Exposing git information at compile time via generated header files
   • Compile flags that I like can (optionally) be carried over by linking with the library
     • Extra warnings, strict standard compliance, and modern C and C++ standards
   • Basic CMake options that I find useful
     • Prevent in-source builds
     • Set a default build type (for single-configuration generators)
6. Flexible error handling code. Designed to immediately terminate program while preserving debugging information.
7. A PID controller implementation
8. Generic interface for doing math with multi-turn encoders
9. Static assertions for C code
10. Serialization library
11. Functions for handling time.
12. Red/Green/Blue LED control that convert to print statements on a host pc
13. Redistribute catch.hpp unit testing framework for use in other projects

Installation

Use vcstool with one of the provided repo files (ssh, http) to clone this repository and the others into a ROS workspace. Then use an isolated build tool like catkin_tools or catkin_make_isolated to compile the workspace.

See Installation for more options and details, including how to install this project without ROS.

Usage

• Use find_package(nuhal) then add nuhal::nuhal to the target_link_libraries
  • This will auto-detect your platform based on the toolchain, host, and cross-compiling status
  • Includes some useful CMake Functions (see comments in nuhal_all/nuhal.cmake for details.
    • nuhal_defaults(type) Sets a default build type and calls
      • nuhal_set_default_build_type(type) Sets the default build type to type for single-configuration generators
      • nuhal_disable_in_source_builds() Requires that the cmake build is in a separate directory from the source tree (to avoid polluting the source with a bunch of cmake-generated files)
      • nuhal_no_lang_extensions() Disables C and C++ language extensions, forcing strict conformance to the standard.
    • nuhal_install(name ...) install a target with the given name. List dependencies after the target name. See nuhal_all/nuhal.cmake for details and requirements.
• Additional Documentation can be found in each platform's README.md. Doxygen documentation is generated with each build and placed in &lt build &gt/doc/index.html.

Adding a Platform

1. Create a new subdirectory called nuhal_platform
2. Use nuhal/nuhal_linux/CMakeLists.txt as a guide for the CMakeLists.txt file
3. If you need to support cross-compiling, use nuhal/nuhal_tiva/PreLoad.txt as a guide for setting a default cross compiler
4. Update /nuhal/nuhal_all/nuhal-config.cmake.in to make it aware of your new library. When a user does a find_package(nuhal) it is this file that is called and it is its responsibility to select the appropriate default nuhal library based on the platform and toolchain

Testing

1. There are automated unit tests that are platform-independent and can be run with make test
2. There are integration tests that can be loaded on the microcontroller in nuhal_tiva/test. Comments at the start of each file describe the expected test behavior