/zephyr-knot-sdk

KNoT SDK based on Zephyr

Primary LanguageC

KNoT Network of Things

Zephyr KNoT SDK provides libraries, tools and samples to make a KNoT application for Zephyr environment.

How to Build it

KNoT Requirements

In order to build a KNoT application, some requirements are needed:

1 - Zephyr

KNoT uses a fork of Zephyr repository.

  • Clone KNoT Zephyr fork

     $ git clone https://github.com/CESARBR/zephyr.git

  • Checkout to KNoT branch

     $ git checkout -b ot-setup origin/ot-setup

  • Set up a Zephyr development environment on your system

    Follow these instructions

  • Set up zephyr environment variables

     $ cd <zephyr-dir>
 $ source zephyr-env.sh

2 - Openthread

KNoT uses Openthread stack.

  • Clone Openthread Github repository: 
     $ git clone https://github.com/openthread/openthread.git
  • Checkout to 2a75d30684654e0348bce9327c6f45f4e9ea71a5 hash 
     $ git checkout -b knot_hash 2a75d30684654e0348bce9327c6f45f4e9ea71a5

3 - nRF5x Command Line Tools

  • Download and install nrfjprog and mergehex cli applications .

To download and more info check this link.

4 - MCUBOOT

  • Requirements

    • python 3
    • virtualenv
    • Zephyr repository (installed at step 2)
    • nrfjprog (installed at step 3)

  • Clone MCUBOOT repository

     $ git clone https://github.com/JuulLabs-OSS/mcuboot.git

  • Checkout to 5e9078f1e0bfed493b4265dd435cccb856cf2d6f hash

     $ cd <mcuboot-dir>
 $ git checkout -b knot_hash 5e9078f1e0bfed493b4265dd435cccb856cf2d6f

  • Create and activate virtual environment

     $ virtualenv -p `which python3` venv
 $ source venv/bin/activate

  • Install python dependencies

     $ pip3 install asn1crypto==0.24.0 cffi==1.11.5 Click==7.0 colorama==0.4.1 cryptography==2.4.2 docopt==0.6.2 idna==2.8 intelhex==2.2.1 pkg-resources==0.0.0 pycparser==2.19 pyelftools==0.25 pykwalify==1.7.0 python-dateutil==2.7.5 PyYAML==3.13 six==1.11.0

  • Set up zephyr environment variables

     $ source <zephyr_dir>/zephyr-env.sh

  • Generate MCUBOOT Makefile

     $ cd <mcuboot_dir>/boot/zephyr
 $ mkdir build && cd build
 $ cmake -DBOARD=nrf52840_pca10056 ..

  • Use config interface to set up signature settings

     $ make menuconfig
 > MCUBoot settings
 > Signature type
 	> Select ECDSA_P256
 > PEM key file
 	> root-ec-p256.pem

    KNoT uses ECDSA_P256 type and root-ec-p256.pem file, available on MCUBOOT root directory. You can change this to your own settings.

  • Build MCUBOOT for zephyr

     $ make

  • Flash MCUBOOT

     $ make flash

5 - Source KNoT environment configuration file.

The environment configuration file is used to set up KNOT_BASE path.

$ cd zephyr-knot-sdk
$ source knot-env.sh

6 - Create KNoT build directory.

KNoT image will be generated on this directory.

$ cd zephyr-knot-sdk
$ mkdir build

Build KNoT application

1 - Application folder

$ cd zephyr-knot-sdk/<app-dir>

You can use the KNoT hello app as an example

2 - Create build directory

$ mkdir build && cd build

3 - Generate Makefile

$ cmake -DEXTERNAL_PROJECT_PATH_OPENTHREAD=<path-to-openthread> -DOVERLAY_CONFIG=${KNOT_BASE}/core/overlay-knot-ot.conf ..

The default (and only supported) board used by KNoT is nrf52840_pca10056.

4 - Build it!

$ make

Build KNoT Setup App

1 - Application folder

$ cd zephyr-knot-sdk/<setup-dir>

2 - Create build directory

$ mkdir build && cd build

3 - Generate Makefile

$ cmake -DBOARD=nrf52840_pca10056 ..

4 - Build it!

$ make

How to flash

1 - Flash MCUBOOT

$ cd <mcuboot-dir>/boot/zephyr/build
$ make flash

For more details check How To Build it -> KNoT Requirements -> MCUBOOT

2 - Merge KNoT Setup and KNoT App images

$ mergehex -m ${KNOT_BASE}/setup/build/zephyr/zephyr.hex ${KNOT_BASE}/apps/hello/build/zephyr/zephyr.hex -o ${KNOT_BASE}/build/slot0_merged.hex

3 - Sign image

For this step, make sure MCUBOOT virtualenv is activated.

$ <mcuboot-dir>/scripts/imgtool.py sign --key <mcuboot-dir>/root-ec-p256.pem --header-size 0x200 --align 8 --version 1.5 --slot-size 0x69000 --pad ${KNOT_BASE}/build/slot0_merged.hex  ${KNOT_BASE}/build/slot0_merged_signed.hex

4 - Flash signed image

$ nrfjprog --program ${KNOT_BASE}/build/slot0_merged_signed.hex --sectorerase -f nrf52 --reset

5 - Use serial monitor

$ minicom -D /dev/ttyACM0 -b 115200

You can install minicom using: $ sudo apt-get install minicom