Working with devices

This codelab series focuses on the Fuchsia emulator (FEMU) as the target device, which is built and distributed with the source tree and runs on your development machine. However, you can also build Fuchsia for supported hardware platforms, such as an Intel NUC.

This section describes some specifics related to working with Fuchsia on physical devices.


Fuchsia defines support for hardware devices by the board name used to configure the build. This includes any hardware-specific packages such as drivers. Recall the fx set command used previously:

fx set workstation_eng.qemu-x64

In this example, qemu-x64 is the board name for FEMU. To build the same product for the Intel NUC, you can modify the set command to use the x64 board.

Note: To determine the Fuchsia board name for your supported hardware, see the device documentation.

fx set workstation_eng.x64

Running fx build will now generate an image for the target device.


Before flashing the operating system, a supported device must have a Fuchsia-compatible bootloader installed. This process is known as bootstrapping the device. Many devices have a compatible bootloader installed from the factory, others may require manufacturer-specific tools to update the bootloader to a compatible version. See the device documentation for more details regarding your specific device.


The process of loading the operating system onto the device is known as flashing. With a device in bootloader mode connected to your workstation, you can use the flash command to flash Fuchsia onto the device.

fx flash

For devices that have already been flashed, you can reboot them from Fuchsia into bootloader mode if you need to flash them again using ffx:

ffx target reboot --bootloader


You can discover and interact with Fuchsia devices from a development machine connected over USB or a local IPv6 network. Fuchsia enables automatic device discovery using DNS Service Discovery (DNS-SD) over multicast DNS (mDNS) and the Overnet mesh protocol.

Host tools such as ffx discover advertising devices and enable host-target interaction with both physical devices and FEMU.

ffx target list
NAME                      SERIAL       TYPE    STATE      ADDRS/IP                            RCS
fuchsia-5254-0063-5e7a    <unknown>    .       Product    [fe80::c357:53e7:aedf:ed95%qemu]    Y

If a target device does not advertise discovery packets or ffx is unable to detect them, you can manage those targets manually using the add and remove commands:

ffx target add {{ "<var>" }}device-ip{{ "</var>" }}:{{ "<var>" }}device-port{{ "</var>" }}

ffx target remove {{ "<var>" }}device-ip{{ "</var>" }}:{{ "<var>" }}device-port{{ "</var>" }}

Once a device is tracked in the target list, ffx interacts with the Remove Control Service (RCS) on the target to enable you to send additional commands.

Diagram showing how ffx is a developer tool that communicates with theRemote Control Service (RCS) on the Fuchsia Device.{: width=“591”}

Note: For a complete list of the developer commands supported by ffx, see the ffx reference.

What's Next?

Congratulations! You've successfully customized and built Fuchsia from source, and have a better understanding for where the key system components live in the source tree.

In the next module, you‘ll learn more about building Fuchsia’s fundamental unit of software:

Fuchsia components