🛠 Premiers pas avec la Radxa ZERO 3W : flasher Radxa OS et démarrer

Objectives

Discover the Radxa ZERO 3W: a Linux SBC in the Raspberry Pi Zero form factor (65 × 30 mm) based on a Rockchip RK3566 quad Cortex-A55 @ 1.6 GHz, featuring Wi-Fi 6 + Bluetooth 5.4, up to 8 GB of RAM, and a USB 3.0 Type-C port. This first tutorial covers the basics: flashing the official image to a microSD card, powering the board correctly (warning: 5 V only!), first boot, and connection.

Hardware

• 1 Radxa ZERO 3W board (1/2/4/8 GB RAM, optional eMMC)
• 1 high-quality microSD card (A2 recommended, 16 GB min.), SDR104 supported
• 1 USB-C power supply 5 V / 2 A minimum (≥ 15 W) — never use a higher voltage: the input accepts only 5 V and a non-compliant power supply "may damage the device" (official warning)
• 1 high-quality USB-C cable (voltage drops caused by thin cables are the primary cause of boot failure listed in the Radxa FAQ)
• Optional: Micro-HDMI display (up to 1920×1080@60 documented), keyboard

Complete Procedure

1. Download the official image from the Radxa download page (docs.radxa.com/en/zero/zero3/download). The officially "fully tested" image is Radxa OS Debian 12 bookworm KDE on the 6.1 BSP kernel (radxa-zero3_bookworm_kde_b1); Radxa warns that other images "may have unknown issues".
2. Decompress the .img.xz then flash with balenaEtcher or dd:

# Linux / macOS — vérifiez le disque avec lsblk ou diskutil list !
unxz -k radxa-zero3_bookworm_kde_b1.img.xz
dd if=radxa-zero3_bookworm_kde_b1.img of=/dev/sdX bs=4M status=progress conv=fsync
sync

1. Insert the microSD card, connect the power supply to USB-C 1 (the one carrying the 5 V + OTG input). Boot order: microSD → eMMC → USB.
2. Log in:

ssh radxa@radxa.local      # Radxa OS : utilisateur radxa / mot de passe radxa
ssh root@radxa.local       # images Debian/Ubuntu : root / radxa
uname -a && cat /proc/device-tree/compatible   # doit contenir radxa,zero-3w

1. Updates and reboot: sudo apt update && sudo apt full-upgrade.

Expected Verification

An LED lights up as soon as the power is correctly supplied. uname -a displays the 6.1 kernel (Radxa BSP), cat /proc/device-tree/compatible returns radxa,zero-3w rockchip,rk3566. With a Micro-HDMI display, the KDE desktop appears in 1080p60. df -h shows the system mounted on the microSD card.

Common Errors

• Powering via USB-C 2: only USB-C 1 provides the 5 V; USB-C 2 is a USB 3.0 host port, it does not power the board.
• Cheap "fast" 9/12/20 V chargers that negotiate poorly: the board accepts ONLY 5 V, a faulty charger causes boot loops — the Radxa boot checklist starts with the power supply and cable.
• Wrong login: radxa/radxa on Radxa OS, root/radxa on Debian/Ubuntu server images.
• Thinking the board is dead on first boot: the first boot after flashing is slow (filesystem expansion); wait a minute before unplugging.
• Confusing it with a Raspberry Pi Zero: Micro-HDMI connector (not mini-HDMI), different microSD/CSI placement — "most accessories" HATs are compatible, not all.
• Flashing an unofficial image without decompressing it: .img.xz must be decompressed (or flashed as-is by Etcher, which handles .xz).