Using Zephyr with Keil Studio and Arm CMSIS Debugger

This repository contains two basic Zephyr examples configured in the zephyr.csolution.yml file for multiple development boards. It uses Keil Studio and the Zephyr west build system to generate the application image.

The Arm CMSIS Debugger provides kernel-aware debugging and views for device peripherals, including the interrupt system. It is used to download and run the application on target hardware.

pyOCD supports runtime behavior analysis in CI workflows using RTT and SystemView.

Overall, Zephyr development is simplified by managing different build configurations, using an intuitive project tree, supporting multi-core configurations, and providing smart editor features such as code completion.

Quick start

1. Install Keil Studio for VS Code from the VS Code marketplace.
2. Follow the Zephyr Getting Started Guide and install Zephyr in the directory $HOME/zephyrproject.
3. Clone this repository (for example using Git in VS Code) or download the ZIP file. Then open the repository folder in VS Code.
4. In VS Code, open the CMSIS View and then the Manage Solution dialog to select the target board and one project.
5. In the CMSIS view, use the Action buttons to build, load, and debug the example on your hardware.

Caution

If you see errors during west build (for example during generating a build system), the west installation or PATH is likely incorrect. Check Settings - Cmsis-Csolution: Environment Variables.

• For Windows, set PATH to $HOME/zephyrproject/.venv/scripts
• For Mac/Linux, set PATH to $HOME/zephyrproject/.venv/bin

Tip

For more information, see the Keil Studio documentation - Work with Zephyr applications.

Add another board

If you use a different board, extend the zephyr.csolution.yml file with:

  # List the packs that define the device and/or board.
  packs:
    - pack: Vendor::DFP
    - pack: Vendor::BSP

  # List different hardware targets that are used to deploy the solution.
  target-types:
    - type: SpecifyName
      board: Vendor::Board_name      # Vendor is optional
      device: Vendor::Device_name    # Vendor and device name are optional

To find the packs, open https://www.keil.arm.com/boards/ and search for your board.

• pack: Vendor::BSP is listed under CMSIS Pack on the Board page.
• pack: Vendor::DFP is listed under CMSIS Pack on the related Device page.

Board name different in Zephyr and CMSIS Pack

Frequently the Zephyr board name does not match. In this case add the variable west-board: as shown below.

Use Zephyr - Supported Boards and Shields and find your board. Under Supported Features the board_name, board_name/soc_name or board_name/soc_name/core_name is listed; this is what you specify with west-board:.

  target-types:
    - type: B-L475-IOT01A
      board: STMicroelectronics::B-L475E-IOT01A
      device: STMicroelectronics::STM32L475VGTx
      variables:
        - west-board: disco_l475_iot1/stm32l475xx

Zephyr Terminal

Keil Studio includes a built-in Zephyr Terminal for running west commands in the IDE. When you open it, it configures the working directory and Zephyr environment for the selected project.

Example west commands:

# Build the project
west build

# Open GUI configuration
west build -t guiconfig

# Generate RAM report
west build -t ram_report

RTT and SEGGER SystemView

SEGGER Real-Time Transfer (RTT) enables real-time data exchange between a target device and a host debugger without requiring an additional UART interface. RTT is also the transport mechanism used for SystemView.

RTT and SystemView are integrated in Zephyr and enabled in the zephyr.csolution.yml file with the west-defs under the build-type: Debug-RTT. RTT and SystemView are currently used for CI testing and can be used with pyOCD as shown below.

Example invocation for target-type: STM32H7B3I-DK:

pyocd load --cbuild-run <path>\out\zephyr+STM32H7B3I-DK.cbuild-run.yml
pyocd run  --cbuild-run <path>\out\zephyr+STM32H7B3I-DK.cbuild-run.yml

The pyOCD run command now outputs test messages to the debug console and collects the file out\zephyr+STM32H7B3I-DK.SVdat, which can be analyzed with SEGGER SystemView.

CI Test Automation

This repository demonstrates a hybrid CI approach: build steps run on GitHub-hosted runners, while hardware execution runs on a self-hosted Raspberry Pi 5 (RPi5) runner connected to a NUCLEO board.

The CI workflow is split into two parts:

• Build_NUCLEO-H563ZI.yaml compiles the selected Zephyr application and produces build outputs that can be consumed by the run workflow.
• Run_NUCLEO-H563ZI.yaml executes on the self-hosted RPi5 runner and uses an attached debug probe to download and execute the image on the target board.

The run workflow uses pyOCD to flash and run the application. To avoid duplicating board configuration in multiple places, the workflow relies on the generated *.cbuild-run.yml file for target information and uses the ID of the connected debug adapter to select the correct probe. Refer to the CMSIS-Toolbox - Run and Debug Configuration for more information.

In the GitHub Actions view of Run_NUCLEO-H563ZI.yaml, you can review the test results:

• The application output is visible in the action log (for example via RTT-based console output).
• The workflow uploads a SEGGER SystemView trace (*.SVdat) as an artifact. This execution trace can be downloaded and analyzed offline.

See Setup Self-Hosted GitHub Runner on Raspberry Pi 5 for details on configuring the self-hosted runner. It explains installing pyOCD and the required DFP and BSP packs for connecting to the target hardware.