## Introduction This document explains how to setup a development environment on macOS for the [DevEdge IoT Developer Kit](/solutions/iotdevkit)'s RTOS and SDK. ## Prerequisites * A MacBook with USB ports. * macOS Monterey version 12.0 or greater. * A serial app. ## Why would I want to implement the instructions in this document? * To be able to upgrade or change the firmware on the [DevEdge IoT Developer Kit](/solutions/iotdevkit). ## Configuration ### Step A Backup your work. If you have previous installation of the T-Mobile RTOS and SDK downloaded on your machine, please save a copy of your work. If not, please skip to Step B. 1. Save a copy of the following folders or all your work in progress will be deleted: 1. $HOME/zephyrproject/DevEdge-IoTDevKit-ZephyrSDK 2. $HOME/zephyrproject/zephyr ### Step B Intall Zephyr. 1. Follow the instructions [here](https://docs.zephyrproject.org/latest/develop/getting_started/index.html) to install Zephyr. 2. Under _Get Zephyr and install Python dependencies_ > Step 4, replace `west init ~/zephyrproject` with `west init -m https://github.com/tmobile/DevEdge-IoTDevKit-ZephyrRTOS.git ~/zephyrproject` ![](https://devedge.t-mobile.com/uploads/image_2022_11_15_11_42_30_9d9bc100b6.png?updated_at=2022-12-15T19:05:16.598Z) 3. The rest of the instructions stay the same. 4. Stop at the _Build the Blinky Sample_ section. ### Step C Clone the T-Mobile Zephyr RTOS and SDK. 1. Open Terminal. 2. Enter the following to download the T-Mobile Zephyr SDK, aka [tmo\_shell](/documentation-hub/iot-developer-kit/interacting-with-the-kit-at-cli-via-tmo-shell):

The release version will change over time.

    cd ~/zephyrproject
    git clone https://github.com/tmobile/DevEdge-IoTDevKit-ZephyrSDK.git
    cd DevEdge-IoTDevKit-ZephyrSDK
    git checkout tmz-sdk-1.19.1-qa

3. Clone the T-Mobile Zephyr RTOS repository:

The release version will change over time.

    cd ~/zephyrproject
    rm -rf zephyr
    git clone https://github.com/tmobile/DevEdge-IoTDevKit-ZephyrRTOS.git zephyr
    cd zephyr
    git checkout tmz-1.19.1-qa

4. Refresh the Zephyr modules by running the following commands.

Do this whenever cloning or pulling the Zephyr repo.

    cd ~/zephyrproject
    west update

5. Stop here if all you wish to do is upgrade your tmo\_shell to the latest version. ### Step D Build your "Hello World" sample then flash the board. 1. Set the build environment by entering the below code into Terminal.

    source DevEdge-IoTDevKit-ZephyrSDK/set-zephyr-build-env

2. Connect to your IoT Developer Kit via serial app. 1. Connect your developer kit to your MacBook. Plug in your USB-C to USB-A cable into the board like in the screenshot below. Ensure that the USB-C end it plugged into the **J-Link USB-C Debug** port. ![](https://devedge.t-mobile.com/uploads/iot_dev_kit_how_to_connect_3e7f450c51.png) 2. Open your serial app. For demonstration purposes we will use [Serial](https://apps.apple.com/us/app/serial/id877615577?mt=12). 3. Select the serial port that is connected to your IoT Developer Kit then click _**Open**_. 4. Under **Terminal** > **Settings** > **Line Settings** > **Baud Rate** make sure the following values are set then click _**OK**_: 1. Baud Rate / Speed - 9600 2. Data Rate - 8 3. Parity - None 4. Stop Bits - 1 5. Flow Control - None ![](https://devedge.t-mobile.com/uploads/image2022_8_1_15_3_44_f313fbe57e.png) 5. At the command line screen press _**Enter**_ on your keyboard. The uart command prompt appears. To learn more about uart, please read the document [Interacting with the Kit at CLI via tmo\_shell](/documentation-hub/iot-developer-kit/interacting-with-the-kit-at-cli-via-tmo-shell). ![](https://devedge.t-mobile.com/uploads/image2022_8_1_15_15_42_30d82df88d.png) 3. In Terminal, build the "Hello World" sample.

    west build $HOME/zephyrproject/zephyr/samples/hello_world -p -b tmo_dev_edge

4. Flash the "Hello World" sample onto the kit.

    west flash

5. If the flash occurred successfully you should see the below screenshot in your serial app. ![](https://devedge.t-mobile.com/uploads/image_2022_11_29_18_49_55_a92cae60bb.png?updated_at=2022-12-15T19:04:03.154Z) 6. Update the code found in the $HOME/zephyrproject/zephyr/samples/hello\_world/src/main.c file to create whatever project you desire. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_11_35_36_9fda5625f5.png?updated_at=2022-12-16T18:39:34.434Z) ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_11_41_56_d307f7ed6b.png?updated_at=2022-12-16T18:39:31.277Z) 7. Flash the board again with your changes.

    west flash

8. Test that your "Hello World" project works. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_11_40_43_0a801bc410.png?updated_at=2022-12-16T18:43:06.334Z) ### Step E Build your "tmo\_shell" sample then flash the board. 1. Set the build environment by entering the below code into Terminal.

    cd ~/zephryproject
    source DevEdge-IoTDevKit-ZephyrSDK/set-zephyr-build-env

2. Enter the below in Terminal to build the [tmo\_shell](/documentation-hub/iot-developer-kit/interacting-with-the-kit-at-cli-via-tmo-shell) sample.

    west build $HOME/zephyrproject/DevEdge-IoTDevKit-ZephyrSDK/samples/tmo_shell -p -b tmo_dev_edge

3. Flash the tmo\_shell sample onto the kit.

    west flash

4. If the flash occurred successfully you should see, in your serial app, your kit going through a series of system checks then finally arrive at the following screenshot. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_17_5_22_b9a7790b9a.png?updated_at=2022-12-16T19:13:45.176Z) 5. Press _**Return**_ on your keyboard to get to the uart command line. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_17_5_49_098cd255ac.png?updated_at=2022-12-16T19:17:13.313Z) 6. Enter `tmo version` to see the version of your SDK. It should be upgraded to tmz-1.19.1-qa. 7. Update the code found in the $HOME/zephyrproject/DevEdge-IoTDevKit-ZephyrSDK/samples/tmo\_shell folder to create whatever project you desire. To understand what the various files in the **tmo\_shell** folder do, please see the [Description of tmo\_shell Source Files](/documentation-hub/iot-developer-kit/interacting-with-the-kit-at-cli-via-tmo-shell) document. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_17_18_38_9e1eca3a77.png?updated_at=2022-12-16T19:26:47.072Z) 8. An example of a source file update is setting the SSID and PSK for Wi-Fi. 1. Open the $HOME/zephyrproject/DevEdge-IoTDevKit-ZephyrSDK/samples/tmo\_shell/prj.conf in your IDE. 2. Find the `CONFIG_TMO_SHELL_SSID` and `CONFIG_TMO_SHELL_PSK` variables. 3. Set the arguments to your Wi-Fi SSID and PSK then save the file. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_17_33_22_e70a474421.png?updated_at=2022-12-16T19:39:14.208Z) 4. Open your Terminal app, change directories to zephyrproject, then set your build environment.

        cd ~/zephryproject
        source DevEdge-IoTDevKit-ZephyrSDK/set-zephyr-build-env

5. Build the tmo\_shell sample.

        west build $HOME/zephyrproject/DevEdge-IoTDevKit-ZephyrSDK/samples/tmo_shell -p -b tmo_dev_edge

6. Flash the sample onto the kit.

        west flash

7. In your serial app, your kit goes through a series of system checks then finally arrives at the following screenshot. Press _**Return**_ on your keyboard to get to the uart command line. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_17_5_49_098cd255ac.png?updated_at=2022-12-16T19:17:13.313Z) 8. Enter `tmo wifi status 2`. Instead of having to enter `tmo wifi connect 2 "" 0 ""` you'll notice that you are already connected to Wi-Fi automatically. ![](https://devedge.t-mobile.com/uploads/image_2022_12_15_17_52_7_f39661f6a9.png?updated_at=2022-12-16T19:57:59.086Z) 9. Update any other source files you desire. 10. Flash the board again with your changes.

     west flash

11. Test that your tmo\_shell project works. ## Troubleshooting * **Issue** - I cannot get my "Hello World' project to work on the IoT Developer Kit. What could be the problem? * **Suggested Solution** - Try doing another `west update` in the the `zephyrproject` folder then flashing the board again.
* **Issue** - What should I do if I receive a "realpath doesn't exist on OSX" error message? * **Suggested Solution** - Run the following command in Terminal.

    brew install coreutils

* **Issue** - I do not have pyelftools installed on my MacBook. Can this cause errors with my development environment? * **Suggested Solution** - Yes it can. Please do the following: * Check the version of Python that is associated with "python3":

        cd ~/zephyrproject
        which python3
        ls -l /usr/local/bin/python3

* Install pyelftools based on that version of python

        pip3.10 install pyelftools

* A screenshot of what that check and install would look like. ![](https://devedge.t-mobile.com/uploads/image_2022_11_15_16_40_33_c7cf4070bd.png?updated_at=2022-12-16T20:18:13.716Z) ## FAQ * **Question** - Will these instructions work on a Windows OS? * **Answer** - No it will not. Please see the [Windows OS for Zephyr Development](/documentation-hub/iot-developer-kit/developer-environment-setup/windows-os-for-zephyr-development) doc for further details.
* **Question** - What do the different files in the $HOME/zephyrproject/DevEdge-IoTDevKit-ZephyrSDK/samples/tmo\_shell folder do? * **Answer** - Please see the [Description of tmo\_shell Source Files](/documentation-hub/iot-developer-kit/developer-environment-setup/description-of-tmo-shell-source-files) document to learn more.

macOS for Zephyr Development