MAKCU Setup Guide - Firmware, Drivers & Wiring

What is the MAKCU?

MAKCU stands for Mouse And Keyboard Control Unit. It's a small PCB with two ESP32-S3 chips that work together. One acts as a USB device (appears as a mouse/keyboard to your gaming PC), the other acts as a USB host (receives input from your real mouse). A CH343 UART chip in the middle provides a serial COM port for your second PC to send commands through.

The big difference from KMBOX NET is true USB passthrough. Your mouse plugs into one side, and the MAKCU clones its USB descriptors (VID, PID, serial number, the works) and presents an identical device to the gaming PC. When your software sends a move command over the COM port, MAKCU injects it into the USB data stream alongside your real mouse input. The gaming PC sees a single device that matches your actual mouse exactly.

Communication happens over serial at up to 4 Mbps. That's slower on paper than KMBOX NET's 100 Mbps Ethernet, but for mouse movement commands the difference is negligible. You're sending tiny packets, not streaming video.

What's in the box

The MAKCU is a bare PCB (no case in most variants) with three USB ports, two buttons, and two status LEDs. Most sellers include two USB cables. Some come pre-flashed with firmware, others ship blank and need to be flashed before first use.

Hardware specs

Component	Specification
Processors	2x ESP32-S3 (dual-core, 240 MHz)
UART Controller	WCH CH343 (up to 4 Mbps)
USB Ports	3x USB-C (or USB-A depending on variant)
Buttons	2x boot/flash buttons (left and right, one per chip)
LEDs	2x status LEDs (left = baud rate, right = host connection)
Polling Rate	1000 Hz (1 ms USB polling interval)
Power	USB bus-powered (USB 1 + USB 2 must both be connected)
Firmware	Open-source (MAKCM project on GitHub)

Understanding the USB ports

This is the most important part of MAKCU setup. Each port has a specific purpose and they are not interchangeable.

To figure out which port is which, orient the board so the USB ports face the ceiling and the top of the MAKCU is facing you. From this angle, USB 3 is on the left, USB 2 is in the center, and USB 1 is on the right. If you flip the board over, you'll see USB 1, USB 2, and USB 3 printed on the back confirming each position. Another easy way to remember: lay the MAKCU flat with the USB ports facing the ground. Your mouse (USB 3) goes on the left side.

Port	Position	Connects to	Purpose
USB 3	Left	Your mouse	Host port. Reads input from your real mouse and clones its descriptors.
USB 2	Center	Second PC	COM port. Serial communication for sending commands.
USB 1	Right	Gaming PC	Device port. MAKCU appears as a mouse/keyboard to this PC.

A mouse must be plugged into USB 3 for MAKCU to work. Unlike KMBOX NET where peripherals are optional passthrough, MAKCU requires a physical mouse on USB 3 because it clones that device's descriptors to present to the gaming PC.

Power rules

USB 1 and USB 2 must both be connected for MAKCU to receive power in normal mode. USB 2 alone provides nothing. This is intentional to prevent back-feeding between two PCs.

LED indicators

Left LED - flashes on boot to show baud rate (1 flash = 115,200 bps, 4 flashes = 4 Mbps)
Right LED - indicates host connection status on USB 3

Wiring it up

In a DMA setup, the MAKCU handles input injection while the DMA card handles memory reading. Both connect to the second PC, but through separate cables.

Mouse

USB

USB 3

MAKCU

USB 1

Gaming PC

USB 2

Second PC

Step by step

Plug your mouse into USB 3 (left port) on the MAKCU.
Connect a USB cable from USB 2 (center port) to any USB port on your second PC.
Connect a USB cable from USB 1 (right port) to any USB port on your gaming PC.
Connect the DMA card in the gaming PC to the second PC via its own cable (separate from MAKCU).
Power on both PCs. The left LED on MAKCU will flash to indicate the baud rate.

Installing the driver

The gaming PC needs zero driver installation. MAKCU appears as a standard USB device matching your mouse's descriptors. All the driver work happens on the second PC.

CH343 driver (second PC)

Download the CH343 driver from WCH's official site.
Right-click CH343SER.INF and select Install (or run the .exe installer if one is provided).
Connect MAKCU's USB 2 (center port) to the second PC.
Open Device Manager and expand Ports (COM & LPT). You should see "USB-Enhanced-SERIAL CH343" with a COM port number.
If the COM port number is 10 or higher, you need to change it. Right-click the CH343 device, go to Properties, Port Settings, Advanced, and set it to a number below 10 (like COM3 or COM5).
Unplug and replug the USB cable to apply the change.

CH340 conflict

If your second PC has a CH340 chip on the motherboard (common on mini PCs), it will conflict with MAKCU's CH343. Many applications default to CH340 over CH343, which blocks the MAKCU connection.

To check, open Device Manager and look under Ports for "USB-SERIAL CH340". If it's there, uninstall it from Device Manager before launching your software each session.

Flashing the firmware

If your MAKCU came pre-flashed, skip this section. If it's unflashed, you'll know because Windows will play the USB connect/disconnect sound in a loop when you plug it in. That's normal and not a defect.

MAKCU has two chips that need to be flashed separately. The left chip (device side) and the right chip (host side). Each has its own button and USB port.

Only connect one USB cable at a time during flashing. Never connect both USB 1 and USB 3 at the same time in flash mode. Always hold the button before plugging in the cable.

Method 1: Web-based flashing (recommended)

Open makcu.com/en/setup in Chrome or Edge (Firefox doesn't support Web Serial).
Disconnect all cables from MAKCU.
Flash the left chip first: Press and hold the left button, plug a USB cable into USB 1 (left port), wait for the connection sound on your PC, then release the button.
Click Connect on the website. Select the left firmware and flash it. Wait for it to finish, then unplug.
Flash the right chip: Press and hold the right button, plug the USB cable into USB 3 (right port), wait for the connection sound, then release.
Click Connect, select the right firmware, and flash it. Wait for completion, then unplug.

Method 2: AIO Tool

Download and launch the AIO Tool (available from the MAKCU Discord).
Hold the left button on MAKCU, plug into USB 1. The tool should show "MCU connected in flash mode". Click Flash Left.
Wait for it to finish, then unplug.
Hold the right button, plug into USB 3. Click Flash Right.
Wait for completion, then unplug.

After the first successful flash, the USB connect/disconnect looping stops permanently.

Baud rate configuration

MAKCU supports two baud rates. Most people won't need to touch this, but it's good to know.

Baud Rate	Speed	Use Case
115,200 (default)	115.2 Kbps	Compatible with all software
4,000,000	4 Mbps	High-performance, sub-millisecond timing

At 115K, a single move command takes longer than one USB poll cycle (1 ms). At 4M, the entire command fits within a single poll window, allowing move + click to be processed together.

Checking your baud rate

Watch the left LED when MAKCU boots. 1 flash means 115,200. 4 flashes means 4,000,000.

Changing the baud rate

Press the left button 4 times quickly while MAKCU is running (USB 1 + USB 2 must be connected). The LED will confirm the new rate. This change is permanent and survives reboots and firmware updates.

Only change the baud rate if your software specifically needs it. A mismatched baud rate will completely prevent communication. Windows Device Manager baud rate settings don't matter here, MAKCU manages its own speed internally.

Common issues

USB connect/disconnect loop when plugging in

Your MAKCU is unflashed. This is the factory-default state of the ESP32-S3 chips. Flash the firmware following the steps above and it stops permanently.

Mouse doesn't work on the gaming PC

Make sure USB 1 is connected to the gaming PC and USB 3 has your mouse plugged in. Try a different USB port. Try a different mouse, not all are compatible (known issues with ROG Omni receiver, Vaxee NP01S V2 wireless dongle, Razer Viper 8K, HyperX Pulsefire Haste, Motospeed V70, and Corsair Nightsword). Make sure both chips are correctly flashed.

CH343 not showing in Device Manager

Reinstall the CH343 driver. Try a different USB port. Make sure you're using a data-capable USB cable (not a charge-only cable). Restart the second PC after driver installation.

COM port number is 10 or higher

Right-click the CH343 device in Device Manager, go to Properties, Port Settings, Advanced, and change it to COM1-COM9. Unplug and replug MAKCU after changing.

CH340 conflict blocking MAKCU

If your second PC has a CH340 chip (common on mini PCs), uninstall it from Device Manager before launching your software. This needs to be done each session.

Software says "MAKCU not found"

Check that the COM port number in your software matches Device Manager. Verify the baud rate matches (check the LED flash count on boot). Make sure no other application is already using the COM port. Only one app can connect at a time.

Baud rate mismatch

If your software can't communicate at all, check the LED flash count on boot. Press the left button 4 times quickly to toggle between 115K and 4M. The MAKCU website auto-detects baud rate, but most other tools expect 115,200.

Mouse works but aimbot doesn't activate

If using PhantomDMA software, make sure the KMBOX/Arduino mode is selected and the COM port is pointed at your MAKCU. MAKCU is backward-compatible with KMBOX B Pro commands, so most software that supports KMBOX B Pro will work without changes.

Tips for best performance

Use motherboard USB ports

Avoid hubs, front panel ports, and extension cables. The CH343 throughput depends on clean USB signaling.

Use 4 Mbps for time-critical applications

At 115K, each command takes longer than one USB poll cycle. At 4M, multiple commands fit within a single 1 ms poll window, enabling frame-perfect input injection.

Close other COM connections

MAKCU allows exactly one application on USB 2 at a time. Close the AIO tool, MAKCU website, and any serial monitors before launching your software.

Keep firmware updated

The MAKCU firmware is actively developed with frequent improvements to passthrough fidelity, command speed, and device compatibility. The v3 update introduced full passthrough which was a big upgrade from earlier versions.

MAKCU vs KMBOX

Here's how MAKCU stacks up against the KMBOX lineup:

Feature	MAKCU	KMBOX NET	KMBOX B+
Communication	Serial COM (4 Mbps)	USB-Ethernet (100 Mbps)	Serial COM (115K baud)
USB Passthrough	True passthrough (clones descriptors)	No (generic HID)	No (generic HID)
Device Emulation	Mirrors your mouse's VID/PID/serial	Generic USB HID	Generic USB HID
Firmware	Open-source (GitHub)	Proprietary (.bin)	Proprietary
Hardware Lock	None	Per-device UUID	None
Display	LEDs only	OLED screen	Screen on B+
Driver (Second PC)	CH343	WCHUSBNIC	CH341
Price	$15-35	$40-55	$25-50

MAKCU's main advantage is true USB passthrough. The gaming PC sees your exact mouse model rather than a generic HID device, making the input injection harder to distinguish at the hardware level. It's also cheaper since the ESP32-S3 is a commodity chip, and the open-source firmware means community-driven improvements with no vendor lock-in.

KMBOX NET's advantage is a faster transport layer (100 Mbps Ethernet vs 4 Mbps serial), encrypted communication, and the convenience of a packaged product with an OLED screen. For most DMA use cases though, 4 Mbps serial is more than enough since you're only sending small mouse movement commands.