lwip-tiva

This is a port of lwIP 2.1.2 to the Texas Instruments TM4C1294NCPDT microcontroller. The goal is to offer a project that can compile without modifying any of the source codes provided by Texas Instruments nor the lwIP source code.

Table of Contents

• lwip-tiva
• Supported Hardware
• Development Environment Setup
  • Required Packages
  • Cross Compiler
  • Flashing Tool
  • Udev Rules
  • Tivaware
  • lwIP Source Code
  • lwip-tiva Source Code
  • Suggested Directory Structure
• Compiling and running

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Supported Hardware

MCU	Tested Board	Bare Metal	RTOS
TM4C1294NCPDT	EK-TM4C1294XL	Supported	No

This port may also work with other microcontrollers and boards. If you were able to run the port with other hardware, please let us know.

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Development Environment Setup

We are using Ubuntu 16.04 as the development environment and the following instructions were tested only for that enviroment.

Required Packages

If you are in a 64 bit system, you have to first execute:

sudo dpkg --add-architecture i386

Then, for all systems, execute:

sudo apt-get update
sudo apt-get install flex bison libgmp3-dev libmpfr-dev \
    libncurses5-dev libmpc-dev autoconf texinfo build-essential \
    libftdi-dev python-yaml zlib1g-dev libtool

Then again, just for 64 bit architectures, execute:

sudo apt-get install libc6:i386 libncurses5:i386 libstdc++6:i386

And for all systems, to flash using USB, you need to install libusb as follows:

sudo apt-get install libusb-1.0-0 libusb-1.0-0-dev

Cross Compiler

We need a cross-compiler to compile the code to the target ARM processor. We are going to use the GNU Arm Embedded Toolchain. The version used in this case study is 8-2018-q4-major. You can download it from here.

Extract the content of the archive to the folder where you want to store the toolchain. We are going to assume that it is going to be extracted to ~/embedded.

mkdir ~/embedded
tar -xvf gcc-arm-none-eabi-8-2018-q4-major-linux.tar.bz2 -C ~/embedded
export PATH=$PATH:$HOME/embedded/gcc-arm-none-eabi-8-2018-q4-major/bin

You probably would like to add the last line to your ~/.bashrc so you don't need to execute it every time.

Flashing Tool

To flash the MCU we are going to use lm4tools:

cd ~/embedded
git clone git://github.com/utzig/lm4tools.git
cd lm4tools/lm4flash/
make
export PATH=$PATH:$HOME/embedded/lm4tools/lm4flash

You probably would like to add the last line to your ~/.bashrc so you don't need to execute it every time.

Udev Rules

Download `` from here and execute the following command.

sudo cp 71-ti-permissions.rules /etc/udev/rules.d/

You will need to unplug the board and restart udev in order to the changes to take place:

sudo udevadm control --reload-rules && udevadm trigger

Tivaware

Texas Instruments provides a set of resources for the Tiva C MCU family and we are going to use it to make it simple to configure the MCU. You can get Tivaware for free here. When writing this tutorial, the available version of Tivaware was 2.1.4.178. To setup Tivaware, use the following:

cd ~/embedded
mkdir tivaware
cd tivaware/
mv ~/Downloads/SW-TM4C-2.1.4.178.exe . 
unzip SW-TM4C-2.1.4.178.exe
make

After executing make you will probably stumble on a problem with one or more of the .ld files. If the command issue an error like arm-none-eabi-ld: section .ARM.exidx overlaps section .data, you must edit the corresponding .ld file (probably from qs-logger example) and change the start of the .data section. You can do this by finding the following line:

.data : AT(ADDR(.text) + SIZEOF(.text))

and replacing it by:

.data : AT(ADDR(.text) + SIZEOF(.text) + SIZEOF(.ARM.exidx))

Compile again using make. This change should settle the problem.

lwIP Source Code

To get lwIP, go here and download the file marked as STABLE-2_1_2_RELEASE. Extract the content of the file to the destination directory. In this case, we are going to use the ~/projects directory. After unpacking it, create a symbolic link called lwip. This will make it easy to test updates of lwIP in the future.

lwip-tiva Source Code

Clone this repository in ~/projects/lwip-tiva.

Suggested Directory Structure

.
├── embedded
│   ├── gcc-arm-none-eabi-8-2018-q4-major
│   ├── lm4tools
│   └── tivaware
└── projects
    ├── lwip
    ├── lwip-STABLE-2_1_2_RELEASE
    └── lwip-tiva

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Compiling and running

After executing the steps described in Development Environment Setup, enter the repository's root directory and execute the command:

./compile.sh

If the command is successful, a directory named build will be created and the compiled examples will be available in that directory. The images to be flashed have the extension .bin.