The Arduino project covered by Hackaday is a keyboard switch, not a complete KVM switch: it routes keyboard input between two computers, but the report says it does not switch video or mouse control. Its reported design uses one Arduino Uno and two Arduino Pro Micros, with Scroll Lock selecting which computer receives the keyboard input.
What the Arduino KVM project does
Hackaday’s report, published April 19, 2020, describes a DIY keyboard switch credited to Nathalis. The word “KVM” can suggest control of a keyboard, video display, and mouse; this reported project handles only the keyboard. It does not provide the video or mouse switching needed to serve as a full KVM.
According to Hackaday’s report, the arrangement uses an Arduino Uno to accept keyboard input and pass serial signals to two Arduino Pro Micros. Each Pro Micro sends keyboard input to a separate computer as standard USB HID input. Scroll Lock selects which output receives input.
How the reported arrangement is organized
- Arduino Uno: accepts keyboard input and handles its incoming serial signals.
- Two Arduino Pro Micros: connected in parallel to receive signals from the Uno; each sends keyboard input to its respective computer as USB HID.
- Scroll Lock: selects the output computer, according to the report.
This describes the architecture as Hackaday reported it, not independently tested wiring or code behavior. The accessible report does not establish which keyboard protocols or operating systems are supported, or how the design behaves with current board revisions.
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What you would need to recreate it
The directly relevant board type for the two USB HID outputs is an Arduino Pro Micro compatible with the ATmega32U4; the design also names an Arduino Uno. The report linked source code and schematics, but the linked GitHub repository could not be accessed when checked for this article. Its wiring, code, license, and current availability therefore remain unverified.
If you look for parts, use “Arduino Pro Micro compatible ATmega32U4 development board” as a search phrase and verify the specifications of the particular listing. The project describes two Pro Micros, not one. An Uno-compatible board is the other named component. The report does not specify exact cable or jumper-wire types, so those should not be treated as confirmed parts or build instructions.
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Is it suitable as a full KVM?
No. It is relevant if the goal is to route keyboard input between two computers. If you also need to switch a monitor and mouse, this build does not meet that requirement as described. A complete KVM switch is a separate category of solution; it is not part of the Arduino project.
The report does not give measured latency or reliability results, a compatibility list, or USB reconnection and enumeration behavior. It also does not establish whether the code can be inspected or adapted today, because the linked repository was inaccessible. Those unknowns make it difficult to assess how the design would work in a particular setup without verified code and schematics.
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