Docs: Firmware Update

Mon, 01 Jan 0001 00:00:00 +0000

Warning

Early versions of the xCore board have a bug in the bootloader which sometimes prevents the board from being detected by the openmower tool.

If you encounter Timeout errors during the firmware installation process, update the bootloader by running: openmower update-bootloader and try again.

To install the firmware to the xCore board, simply run: openmower update-firmware. The openmower tool will read your environment variables, download the appropriate firmware binary and upload it to the xCore board via Ethernet.

The expected output is shown below:

Example output for openmower update-firmware command.

Docs: Flashing the CM4 eMMC

Mon, 01 Jan 0001 00:00:00 +0000

CM4 with eMMC only

This guide applies only to CM4 variants with onboard eMMC storage. The CM4 Lite variant has no eMMC — it uses a microSD card instead and does not require this process.

Check your CM4 model number: variants with eMMC have the storage size in the name (e.g. CM4008032 = 32 GB eMMC). Lite variants are explicitly labelled “Lite” (e.g. CM4008000).

The CM4 with eMMC has onboard flash storage instead of a microSD slot. To flash a new image, you need to put it into USB boot mode so it appears as a mass storage device on your computer.

This guide covers the OpenMower-specific steps. For full reference, see the official Raspberry Pi documentation .

Prerequisites

A host computer (Linux, Windows, or macOS)
A micro USB cable (connected to the USB port on the xCore board)
The OS image you want to flash (e.g. OpenMower OS)

Step 1: Enter USB boot mode

The xCore board has an Rpi Boot button (left of the two buttons, label printed below the CM4 slot).

Hold the Rpi Boot button.
While holding it, connect power to the xCore board (or plug in the micro USB cable to your host computer).
Release the button once powered.

The CM4 is now in USB boot mode.

Step 2: Install rpiboot on your host computer

sudo apt install rpiboot
sudo rpiboot

Download and run the installer from the usbboot releases page .
Reboot your computer after installation.
With the CM4 in USB boot mode, open Start → rpiboot - Mass Storage Gadget.

Build rpiboot from source, then run:

rpiboot -d mass-storage-gadget64

See the usbboot repository for build instructions.

Within a few seconds the CM4’s eMMC will appear as a USB mass storage device on your computer.

Tip

If the device is not recognised, avoid USB hubs — connect the micro USB cable directly to your computer.

Step 3: Flash the image

Use Raspberry Pi Imager to write your OS image to the eMMC device. Select the eMMC as the target storage — it will appear like any other USB drive.

Alternatively, use dd on Linux/macOS:

sudo dd if=your-image.img of=/dev/sdX bs=4MiB status=progress oflag=sync

Replace /dev/sdX with the actual device path of the eMMC. Double-check this before running.

Step 4: Boot from eMMC

Once flashing is complete, disconnect the micro USB cable and power-cycle the board. The CM4 will boot from the newly flashed image.

Docs: External Wifi Antenna

Mon, 01 Jan 0001 00:00:00 +0000

After adding the external antenna, you need to tell the Raspberry Pi CM4 to use the external antenna instead of the built-in one.

Terminal Cast

How to edit the antenna configuration

Instructions

You can do this by:

Run sudo nano /boot/firmware/config.txt
Scroll Down to the [cm4] section and:
- Comment # dtparam=ant1
- Uncomment dtparam=ant2
Save CTRL + O and Exit Nano CTRL + X
Reboot the OS by running sudo reboot

OpenMower — Open Source RTK GPS Robotic Mower – Installation

Docs: Firmware Update

Warning

Docs: Flashing the CM4 eMMC

CM4 with eMMC only

Prerequisites

Step 1: Enter USB boot mode

Step 2: Install rpiboot on your host computer

Tip

Step 3: Flash the image

Step 4: Boot from eMMC

Docs: External Wifi Antenna

Terminal Cast

Instructions