Zephyr is a scalable real-time operating system (RTOS) supporting multiple hardware architectures, optimized for resource-constrained devices, and built with safety and security in mind.

Compatible

FoBE Zephyr SDK is a module designed for FoBE hardware, extending the official Zephyr repository with enhanced features and optimizations.

Setup

important

Before you start, make sure you have Python installed on your system.

1. Open Visual Studio Code and create a new folder for your project.

2. Create a virtual environment for the project

   # Create a virtual environment
   python3 -m venv .venv
   
   # Activate the virtual environment
   source .venv/bin/activate
   
   # Install the required packages
   pip install west

3. Create .west/config file in the project directory with the following content

   [manifest]
   path = app
   file = west.yml
   
   [zephyr]
   base = zephyr

4. Create app folder and add some files like

   .west/
   └── config
   app/
   ├── CMakeLists.txt
   ├── prj.conf
   ├── west.yml
   └── src
       └── main.c

   Add CMakeLists.txt file with the following content

   cmake_minimum_required(VERSION 3.20.0)
   find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
   project(app)
   
   target_sources(app PRIVATE src/main.c)

   Add prj.conf file with the following content

   CONFIG_GPIO=y

   Add west.yml file with the following content

   manifest:
   remotes:
       - name: zephyr
           url-base: https://github.com/zephyrproject-rtos
       - name: fobe
           url-base: https://github.com/fobe-projects
   projects:
       - name: zephyr
           remote: zephyr
           revision: v4.2.0
           path: zephyr
           import: true
       - name: fobe-zephyr-sdk
           remote: fobe
           path: fobe
           revision: main

   Add src/main.c file with the following content

   #include <stdio.h>
   #include <zephyr/kernel.h>
   #include <zephyr/drivers/gpio.h>
   
   /* 1000 msec = 1 sec */
   #define SLEEP_TIME_MS 1000
   
   /* The devicetree node identifier for the "led0" alias. */
   #define LED0_NODE DT_ALIAS(led0)
   
   /*
   * A build error on this line means your board is unsupported.
   * See the sample documentation for information on how to fix this.
   */
   static const struct gpio_dt_spec led = GPIO_DT_SPEC_GET(LED0_NODE, gpios);
   
   int main(void)
   {
       int ret;
       bool led_state = true;
   
       if (!gpio_is_ready_dt(&led)) {
           return 0;
       }
   
       ret = gpio_pin_configure_dt(&led, GPIO_OUTPUT_ACTIVE);
       if (ret < 0) {
           return 0;
       }
   
       while (1) {
           ret = gpio_pin_toggle_dt(&led);
           if (ret < 0) {
               return 0;
           }
   
           led_state = !led_state;
           printf("LED state: %s\n", led_state ? "ON" : "OFF");
           k_msleep(SLEEP_TIME_MS);
       }
       return 0;
   }

5. Install and configure the Zephyr SDK

   # Update the west workspace in your project directory, it will download the Zephyr SDK and other dependencies
   west update
   
   # Install packages required for building the project
   west packages pip --install
   
   # Install the Zephyr SDK
   west sdk install

6. Build and flash the project

   Double-click the reset button on the device to enter bootloader mode, then run the following commands in the terminal

   # Build the project for the FoBE board
   west build -b <board_name> ./app
   
   # Flash the project to the board
   west flash --runner uf2

   tip

   Replace <board_name> with the appropriate board name for your FoBE device. For example, for the FoBE Quill nRF52840 Mesh board, use quill_nrf52840_mesh.

   important

   Different boards may have different flash methods. Please refer to the specific board documentation for detailed instructions on how to enter bootloader mode and flash the firmware.

   Now you have a simple LED blinking example (Zephyr Standalone project) running on the board.

   
   
   

More information about the Zephyr can be found in the Zephyr documentation.

You can also explore the FoBE Zephyr SDK for more details on using the FoBE Zephyr SDK.