Community Edition · Available to order
HDMI to CSI Adapter
An RK628H video bridge that turns an HDMI signal into a MIPI CSI-2 stream your board can capture directly, at up to 4K 30. It exposes EDID, which is how WarpKVM tells a source what resolution and refresh rate to send. Two versions, one bridge and the same modes: a 30-pin for the Firefly ROC-RK3576-PC, and a 22-pin for the Luckfox Aura and other boards with a standard Rockchip camera connector. Choose the fitment at checkout.
Fitment
In stock · ships in 1 to 2 business days · 30-day returns · US shipping from $6.95
Capabilities
What it does.
4K 30 over MIPI CSI-2
3840×2160 at 30 fps from a single 4-lane port, measured on hardware rather than read off a datasheet. 1080p60 and below run clean on stock firmware.
EDID control
The host can read and rewrite the EDID this board presents. That is how you ask a machine for 120 or 144 Hz instead of accepting whatever it offers.
HDMI audio, decoded on board
An on-board DAC recovers the audio stream and puts it out as analogue stereo on a 3.5 mm jack and two wafer connectors.
Scope
What you get, and what you'll need.
In the box
One adapter with the connector you chose fitted, 30-pin or 22-pin, brought up on a real host and tested before it is packed. That is the whole shipment.
Not included
No host board, no FPC cable, no HDMI cable, no power supply. The RK3576 board in the third photograph is shown for context only.
You'll need
A host with a free 4-lane MIPI CSI-2 input and the matching FPC cable: 30-pin for the Firefly ROC-RK3576-PC, 22-pin for the Luckfox Aura. Validated end to end on the Firefly with factory firmware.
Questions
Before you buy.
No. You are buying the adapter on its own. The RK3576 board and the FPC cable in the connection photograph are there to show how it all fits together.
Per-lane bandwidth. This adapter routes one of the RK628H's two CSI ports, and 4K60 over a single 4-lane port needs 2376 Mbps per lane, above what the bridge will drive. Split across both ports it fits: our DIY kit's carrier board routes the same bridge that way. As a standalone adapter we have not built a dual-port version yet. Get in touch if you need it.
First pick the connector. The 30-pin fits the Firefly ROC-RK3576-PC we validated it on; the 22-pin fits the Luckfox Aura (RV1126B) and other boards that bring MIPI CSI out on the common 22-pin Raspberry-Pi-style connector. The bridge, the driver, and every capture mode are identical between them, so only the FPC connector and the host differ. On the software side, the same RK628H driver ships in the Rockchip BSP for the RK3566, RK3568, RK3588 and RK3588S, so those should work, though we have not tested them all. Not the Raspberry Pi. Check your board's camera connector, and ask us before ordering if you are unsure.
You have 30 days from delivery to send it back for a full refund if it is unused and in its original packaging, and you can cancel for free any time before it ships. If a board arrives dead or fails in normal use within a year, we replace it and cover postage both ways. Full details in our returns policy.
Technical data
Specifications.
Video
- Bridge chip
- RK628H
- HDMI input
- Up to 4K @ 60, YUV420
- HDMI version
- 1.4 and 2.0, 8/10-bit per component
- CSI output
- 3840×2160 @ 30 · 1920×1080 @ 144 / 120 / 60 · 1280×720 @ 60 · 720×480 @ 60
- Output colour
- YUV422 only, fixed in silicon
Board
- Dimensions
- 46.25 × 30 mm (30-pin) · 45 × 30 mm (22-pin)
- Mounting
- 4× M2.5 on a 27 × 25 mm pattern (30-pin) · 30 × 23 mm (22-pin)
- Power
- 5 V via the FPC connector
- Audio out
- Analogue stereo line level: 3.5 mm jack plus 3-pin and 2-pin wafer
Interface
- Connector
- 30-pin or 22-pin, 0.5 mm pitch (choose at checkout)
- Lanes
- 4 data lanes plus 1 clock lane
- Control
- I2C at 1.8 V, 2.2 kΩ pull-ups
- Signals
- Reset in, interrupt in, HDMI-detect out
- Standard
- MIPI D-PHY v1.2
Notes
- Input vs output
- The chip accepts 4K @ 60 in. What it can emit over CSI is the figure above.
- Above 60 Hz
- 1080p at 120 and 144 need our patched driver and a device tree change. 4K30 and 1080p60 work on stock Rockchip firmware.
- Audio path
- HDMI audio is decoded on-board to analogue. It does not reach the host, so it cannot be recorded or streamed.
- Measured on
- Rockchip RK3576, 300 to 400 frames per mode.
Measured, not estimated
Every mode, on real hardware.
Captured on a Firefly ROC-RK3576-PC, 300 to 400 frames per mode, frame rate and error count read straight off the pipeline.
| Mode | Stock firmware | WarpKVM kernel |
|---|---|---|
| 3840 × 2160 @ 30 | 30.00 fps | 30.10 fps |
| 1920 × 1080 @ 144 | Capture hangs | 143.98 fps |
| 1920 × 1080 @ 120 | Capture hangs | 120.00 fps |
| 1920 × 1080 @ 60 | 60.00 fps | 60.00 fps |
| 1280 × 720 @ 60 | Not tested | 60.00 fps |
| 720 × 480 @ 60 | Not tested | 60.01 fps |
4K30 and 1080p60 work the moment you plug it in. Anything above 60 Hz needs our kernel patches and one device tree property, which we will send you free. The documentation tab has the detail.
Read first
Documentation.
Everything we know about this board is published. If something you need is missing, ask and we will write it down.
Setup guide
Connecting the adapter, verifying the bridge is bound, viewing the capture, high-refresh capture, and the full troubleshooting list.
Product specification
WKVM-SPC-001 Rev. A. Interfaces, validated modes, host requirements, mechanical drawing, and the limitations of the stock driver.
RK628H datasheet
Rockchip's datasheet for the bridge chip, for designing your own carrier or writing a driver. Hosted on a community mirror rather than by Rockchip.
