Arduino Due · Dual PC
A dual-PC setup using the Due’s two USB ports. No serial adapter or jumper wires.
Install Knife.Baby on your second PC. The gaming PC runs the game and OBS. The Due uses one USB port for each PC, so this setup needs no serial adapter and no jumper wires.
Video flows back: gaming PC / OBS → Ethernet / NDI → second PC / Knife.Baby. Connect your mouse to the second PC.
Have these ready.
- Arduino Due
- Two micro-USB data cables
- Two Windows PCs on a wired network
Install Knife.Baby on the second PC
Download Knife.Baby from Downloads, sign in and choose your game. Select Dual PC → Arduino Due.
Flash through the Programming port
Connect the Due’s Programming port, the micro-USB connector next to the power jack, to your second PC. Knife.Baby puts the board into flash mode. Keep it connected until the firmware has been written and checked.
Connect the Native port to the gaming PC
Leave the Programming port → second PC cable connected. Connect the Native port, next to the reset button, to the gaming PC with a second micro-USB data cable.
The Knife.Baby board card should discover the board, for example Due · COM12, and show Connected after it responds.
Configure OBS on the gaming PC
Install the capture software
On your gaming PC, install the versions specified for this setup:
- OBS Studio 31.1.0
- DistroAV 6.0.0
- NDI 6 Runtime, from the DistroAV installation instructions
If you need to replace an existing OBS installation, back up your profiles and scenes first. These are the setup versions in this guide; check Knife.Baby’s release notes before changing them.
Capture the game
- Add a Game Capture source for your game. Use Game Capture rather than Display Capture.
- Right-click the source → Transform → Reset Transform.
- Choose Transform → Center to Screen. Do not use Fit to Screen for this setup.
Set the video format
Open Settings → Video:
- Base (Canvas) Resolution: your Knife.Baby scan size, for example 640 × 640.
- Output (Scaled) Resolution: the same scan size.
- If different games use different scan sizes, use the largest required size.
- FPS: Fractional FPS Value → 240 / 1 to start, if your PCs and network can sustain it.
Open Settings → Advanced:
- Process Priority: High
- Color Format: NV12
- Color Space: Rec. 709
- Color Range: Limited
Send the stream
Open Tools → DistroAV NDI Settings:
- Turn Main Output on.
- Name the output Knife.Baby.
- Leave Preview Output off.
Turn off the OBS preview, run OBS as administrator, and connect both PCs by Ethernet to the same router.
Keep the highest frame rate that stays smooth. Watch the stream stutter reading in Knife.Baby’s Overview. If stutter stays high, lower OBS to 144 / 1, then lower it further if needed. A stable stream is more useful than an unstable high frame rate.
If OBS locks the Video settings, turn DistroAV’s Main Output off, change the settings, then turn it on again.
Find the stream and enable Passthrough
Back on your second PC, the final Knife.Baby setup step should find the stream named Knife.Baby. Check the received size and frame rate.
If discovery fails, choose Can’t find it? and enter the gaming PC’s IP address. Allow OBS and Knife.Baby through Windows Firewall for your private network.
Plug your mouse into the second PC. To control the gaming PC, enable Passthrough on the board card or press F7. Some laptops require Fn + F7. Press it again to return mouse control to the second PC.
Test Passthrough with the board’s mouse-output USB connection plugged into the gaming PC. If its output loops back into the same PC running Knife.Baby, cursor movement can freeze. Press F7 again to leave Passthrough.
Let’s get you connected.
The board card stays Not connected
Check both connections: Programming port → second PC, and Native port → gaming PC. Try different data-capable cables; some micro-USB cables only charge.
The stream does not appear
Confirm DistroAV’s Main Output is on, both PCs are on the same network, and the private-network firewall rules allow OBS and Knife.Baby. If discovery does not cross your subnets, enter the gaming PC’s IP address under Can’t find it?.
The stream stutters or feels delayed
Lower OBS’s FPS, use Ethernet instead of Wi-Fi, and run OBS as administrator. Check the stutter reading after each change.
I cannot change OBS video settings
Turn off DistroAV’s Main Output, change your video settings, then turn the output back on.