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Peter Wittich edited this page Oct 12, 2020 · 19 revisions

Downloads

The following assumes you are using a unix-based platform (Linux, MacOS, or WSL on Windows). That means you have access to make, git, etc, and is intended for development on a personal machine. The Cornell LNX machines (such as lnx4189) already have the appropriate tools installed.

Download the following:

If you want to use an IDE there are two options.

  • Eclipse CDT. This is the basic Eclipse IDE for C/C++ programming. To make things easier it is suggested to grab it from this specialized version for microcontrollers. Install the binary from 'downloads' on this page. This includes not just the Eclipse and CDT but also specializations for working with ARM microcontrollers.
  • An alternative is Visual Studio Code. This more modern IDE is good but takes some tweaking to get it to work with makefile projects. You need to generate a compile_commands.json file to make cross-references work properly, and also need to define custom rules to invoke make.

Source code management with git/GitHub

The code for the MCU must be developed on a branch that is not the master branch. The master branch is protected -- you can only submit pull requests to the master branch, not push directly to master.

The pull requests undergo a continuous integration build as described in the top level README file and then the PR must be reviewed by someone before being merged.

Best practice is to rebase the branch to the master before submitting a pull request.

Getting the code

The code can be pulled from the repo as follows.

git clone [email protected]:apollo-lhc/cm_mcu.git

At this point all the usual git commands are available. You'll want to make your own branch to develop there. Easiest thing is to make the branch on github (e.g. with the branch my-branch-name) and then switch to the branch in your local repo via

git checkout my-branch-name

on your local machine.

Building the code

You need to make sure the downloaded compiler is in your path. Then, in your shell, you need to set up one environment variable to point the build at your FreeRTOS code

export FREERTOS_ROOT=/base/of/install/FreeRTOS/Source

The last two parts of the above directory path are internal to the FreeRTOS source code tree.

To build the code you just type

make

Possible flags to consider are DEBUG=1 for a debug build and VERBOSE=1 to see how the compile commands are invoked. All other regular make options should work too.

make -j DEBUG=1 VERBOSE=1

for a debug build with full screen printout.

Setting up the Eclipse project

  1. After downloading the code, start eclipse and import the code via File>New>Makefile Project with existing code.
  2. Set the build to use the ARM compiler by opening the project preferences, navigate to C/C++ Build>Settings, and select "Gnu Tools for ARM Embedded". (If you don't have this option you need to install the ARM for embedded extension for Eclipse)

The build should mostly work now, but some tweaks need to be added to get rid of the red squiggly lines in the IDE.

  1. In the project settings, click on C/C+++ General>Paths and symbols.
  2. Under 'includes' for C the following include directories.

creating a compile_commands.json

The python package compiledb can be used for this purpopse. Once installed (e.g. with pip) call it with

compiledb make -w VERBOSE=1

Both the -w flag and the verbose build are required.

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