RAD·KVM
MODEL Q6A-KVM · REV 0.1
OPEN SOURCE · BUILT BY HAND
KVM over IP · Radxa Dragon Q6A

A KVM-over-IP you can hold in one hand.

It takes a headless machine's HDMI in as video and gives back keyboard, mouse and a virtual drive — in your browser, on one small board. No cloud, no account, nothing installed on the far end.

J1install
A · build
$

Clone & run on RadxaOS — builds the driver, USB gadget and web UI from source, on the board.

B · flash
↓ rad-kvm-q6a.img.gz1.1 GB

Pre-baked card image. Write it with balenaEtcher or Raspberry Pi Imager, boot on Ethernet — no shell needed.

→ reboot, then open http://rad-kvm.local:8000 and set a password.

U1overview

A whole KVM, soldered to nothing

RAD-KVM turns a Radxa Dragon Q6A into a PiKVM-class appliance. It captures the target machine's HDMI through a Toshiba bridge over MIPI CSI-2, and presents itself as a USB keyboard, mouse and flash drive on the other end — so you get the live screen and full control, plus Wake-on-LAN, shortcuts and macros, from any browser on your network.

Built the slow way: a vendored, patched kernel driver; a device-tree merge the bootloader actually honours; one dependency-free Go binary serving the interface. The full bring-up — every dead end included — is written up in the repo.

U2signal path
target machine your laptop / phone ┌──────────┐ HDMI ┌─────────┐ CSI-2 ┌───────┐ MJPEG ┌─────────┐ │ headless │ ──────► │ TC358743 │ ──────► │ Q6A │ ───────► │ :8000 ui │ │ PC │ └──────────┘ └───┬───┘ over lan └────┬─────┘ │ │ ◀───────── USB HID gadget ──────┘ │ └───────────┘ keyboard · mouse · drive ◀────── your clicks ─────┘

Video out one way, control back the other, over a single network. The target runs no software and never knows it isn't a real monitor and keyboard.

U3spec
board
Radxa Dragon Q6A — Qualcomm QCS6490, GbE, WiFi 6
capture
HDMI → TC358743 → MIPI CSI-2, up to 720p60 / 1080p30
control
USB gadget — keyboard, absolute mouse, mass-storage
video
MJPEG over HTTP, ~6% of one core
software
one Go binary · single-user auth · zero external deps
tools
Wake-on-LAN · shortcuts · macros · type & paste
find it
rad-kvm.local:8000 over mDNS — no IP hunting
licence
open source — read it, fork it, keep it
U4boards

What it runs on

RAD-KVM is written for, and tested on, one board. The recipe needs two things from any host: a MIPI CSI input for the HDMI bridge, and a USB OTG / peripheral port for the gadget. Other boards have both — but a different chip means the platform glue (camera pipeline, driver, device tree, boot) has to be ported first.

tested

Radxa Dragon Q6A — Qualcomm QCS6490

The reference board. Everything on this page runs here, end to end.

untested

Radxa ROCK 5T — Rockchip RK3588

Has the two things that matter (2× MIPI CSI + USB-C OTG), but a different SoC — so it'd need a port of the Qualcomm-specific bits. Not yet attempted.

unverified

ROCK 5U & other CSI + OTG boards

Plausibly portable if a board pairs a CSI input with a USB OTG port — RK3588 ROCK models, others. Specs unconfirmed; treat as a starting point, not a promise.