This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

Raptor Lake CRB


Raptor Lake processor is a 13th generation 64-bit multi-core processor built on a 10-nanometer technology process. Raptor Lake is based on a Hybrid architecture, utilizing P-cores for performance and E-Cores for efficiency.

Raptor Lake S and Raptor Lake P processor lines are supported.

The S-Processor line is a 2-Chip Platform that includes the Processor Die and Platform Controller Hub (PCH-S) Die in the Package.

The P-Processor line is a 2-Die Multi Chip Package (MCP) that includes the Processor Die and Platform Controller Hub (PCH-P) Die on the same package as the Processor Die.

For more information about Raptor Lake Processor lines, P-cores, and E-cores please refer to RPL.

Raptor Lake Customer Reference Board (RPL CRB) is an example implementation of a compact single board computer with high performance for IoT edge devices. The supported boards are intel_rpl_s_crb and intel_rpl_p_crb.

These board configurations enable kernel support for the supported Raptor Lake boards.


General information about the board can be found at the RPL.

Supported Features

In addition to the standard architecture devices (HPET, local and I/O APICs, etc.), Zephyr supports the following Raptor Lake-specific SoC devices:

  • SMBus

UART Serial Port Support

The Raptor Lake UARTs are NS16550-compatible. Baud rate of 115.2kbps is supported on uart0.

Connections and IOs

Refer to the RPL for more information.

Programming and Debugging

Use the following procedures for booting an image on an RPL CRB board.

Build Zephyr application

  1. Build a Zephyr application; for instance, to build the hello_world application on Raptor Lake S CRB:

    # From the root of the zephyr repository
    west build -b intel_rpl_s_crb samples/hello_world


    A Zephyr EFI image file named zephyr.efi is automatically created in the build directory after the application is built.

Booting the Raptor Lake S CRB Board using UEFI

Preparing the Boot Device

Prepare a USB flash drive to boot the Zephyr application image on a board.

  1. Format the USB flash drive as FAT32.

    On Windows, open File Explorer, and right-click on the USB flash drive. Select Format.... Make sure in File System, FAT32 is selected. Click on the Format button and wait for it to finish.

    On Linux, graphical utilities such as gparted can be used to format the USB flash drive as FAT32. Alternatively, under terminal, find out the corresponding device node for the USB flash drive (for example, /dev/sdd). Execute the following command:

    $ mkfs.vfat -F 32 <device-node>


    Make sure the device node is the actual device node for the USB flash drive. Or else you may erase other storage devices on your system, and will render the system unusable afterwards.

  2. Copy the Zephyr EFI image file zephyr/zephyr.efi to the USB drive.

Booting Zephyr on a board

Boot the board to the EFI shell with USB flash drive connected.

  1. Insert the prepared boot device (USB flash drive) into the board.

  2. Connect the board to the host system using the serial cable and configure your host system to watch for serial data. See board’s website for more information.


    Use a baud rate of 115200.

  3. Power on the board.

  4. When the following output appears, press F7:

    Press <DEL> or <ESC> to enter setup.
  5. From the menu that appears, select the menu entry that describes that particular EFI shell.

  6. From the EFI shell select Zephyr EFI image to boot.

    Shell> fs0:zephyr.efi
  7. When the boot process completes, you have finished booting the Zephyr application image.