Leonardo with Moonlink
About 3 minutes to read
#π₯ Video Tutorial
#1) Connect CP2102 to Arduino
π Hardware Setup:
- Grab 3 female to male jumper cables.
- Plug one end of the jumper into the "TXD" pin on the CP2102 and the other end into the "RX0" pin on the Arduino Leonardo.
- Plug one end of the jumper into the "5V" pin on the CP2102 and the other end into the "5V" pin on the Arduino Leonardo.
- Plug one end of the jumper into the "GND" pin on the CP2102 and the other end into the "GND" pin on the Arduino Leonardo (next to the 5V pin).
- Plug the CP2102 into the 2nd PC.
- Plug the Arduino into the gaming PC.
You have successfully completed the hardware setup!
#2) Check COM Port for CP2102
π» Software Setup:
- In the Moonlink folder, open the siliconlabs folder.
- Right-click silabser.inf and hit install.
- Press the Windows Key and type "Device Manager".
- Under "Ports (COM & LPT)", find "Silicon Labs CP210x USB to UART Bridge". The COM port will be next to the name.
- Under Hardware, go to Properties. In Properties, click on "Change settings". Under Power Management, untick "Allow the computer to turn off this device to save power."
f the COM port doesn't show up, follow these steps again and install the CP210x Universal Windows Driver. You can download the driver from the following link:
#3) Mouse Software Setup
π±οΈ Mouse Setup: Make sure to download mouse software on the 2nd PC and set the mouse polling rate to 1k. Ensure that "Enhance Pointer Precision" is turned off on the 2nd PC.
#4) Run the Program
π Program Setup:
- Open Moonlink.exe in the Moonlink folder located in
C:\moonlink\. - Register or login.
- If you bought a Color or AI sub, you will use that key.
- The GUI should pop up.
- Unplug your mouse from the Gaming PC and plug it into the Script PC.
- Ensure only ONE mouse is plugged into the Script PC, or Moonlink might get confused.
- To enter capture mode, click "Enter Capture Mode".
- To exit capture mode, hit the ESC key on your keyboard.
#π οΈ Quick Fix: Mouse Not Moving in Capture Mode
If your mouse isnβt moving on the Gaming PC after entering Moonlink Capture Mode, follow these quick troubleshooting steps:
#π 1) Reflash the Arduino
π¨ If flashing fails or gets stuck:
- Make sure the Arduino is in bootloader mode (Press Reset before flashing).
- If the COM port doesnβt appear, try another USB port.
#π 2) Check Cable & Connection Quality
- Use a high-quality USB cable for the Arduino (cheap cables can cause data loss).
- If using a USB hub, plug the Arduino directly into the PC.
#π 3) If Using Leonardo + CP2102, Secure the Jumpers
πΉ Check that all jumper wires are securely connected:
- TXD (CP2102) β RX0 (Arduino Leonardo)
- 5V (CP2102) β 5V (Arduino Leonardo)
- GND (CP2102) β GND (Arduino Leonardo)
β If unsure, replug each jumper and test again.
#π 4) Power Cycle Everything
β Steps to Reset & Power Cycle:
- Unplug the Arduino from the PC.
- Unplug any extra hardware (CP2102, USB hubs, etc.).
- Wait 5 seconds, then plug everything back in.
- Open Moonlink.exe β Click Enter Capture Mode again.
#π TL;DR - Quick Fix Checklist
β
Reflash Arduino firmware
β
Use a high-quality USB cable
β
Check that CP2102 jumpers are secure (if using Leonardo)
β
Unplug and replug the Arduino & all hardware
If the issue still persists, post in support chat with screenshots of:
β
Device Manager (Ports & COM LPT section)
β
Firmware flashing output
This should resolve 90% of cases where the mouse isnβt moving in Capture Mode. π



Stuck on a step? Ask in the Moonlight Discord and a staff member will help.