Updating MAKCU to v4 with the MAKCU Toolkit

The MAKCU Toolkit is MAKCU's own free Windows app for firmware updates. It tells you when to unplug and replug each cable, checks the firmware and writes the update. This page follows MAKCU's Toolkit guide in our own words. If the Toolkit ever says something different from this page, do what the Toolkit says.

Your MAKCU works on the firmware it came with, and ours arrive on v3. Update when your software needs v4, or when we ask you to in a ticket. If you run a keyboard through MAKCU, ask in a ticket first, because makcu.com lists keyboard passthrough on v4 as coming soon.

Before you start

Which port is which

MAKCU's ports are printed on the board as USB1, USB2 and USB3, so go by those labels. With the ports facing you, USB1 is on the left, USB2 in the middle and USB3 on the right.

• USB1 goes to your main PC.
  It's the side your game PC sees as a mouse.
• USB2 goes to the PC running the Toolkit.
  This is MAKCU's management port, and it's the one that shows up as a CH343 COM port. On a normal setup that's your second PC.
• USB3 is your mouse.
  Leave it empty for the whole update and plug your mouse back in at the end.

Only have one PC? Plug USB1 and USB2 both into it.

Get the MAKCU Toolkit

Download it from makcu.com/toolkit, MAKCU's own page. We don't host it, so you always get their current version, and the Toolkit keeps itself up to date after that.

Update the firmware

This is the normal update. It works when the Toolkit can read the firmware MAKCU is on now. Don't hold any button on the board for this.

1. Open the Toolkit and press Check device and update on the Home screen.
2. Close your other tools and unplug every MAKCU cable, the mouse too. Tick the box and press Check disconnection. The check takes about 10 seconds.
3. Plug in USB1 first, then USB2. Leave USB3 empty. Tick the box and press Check device.
4. On the device page, press Update firmware. Check the version you're on and the version it's going to, then press Download and verify.
5. The Toolkit asks you to unplug and replug again. Do it the same way, USB1 first, then USB2, with USB3 empty.
6. At Ready to update, press Start update. Keep USB1 and USB2 plugged in and leave the cables alone.
7. Wait for Update complete and checked. Then plug your mouse back into USB3 and make sure it moves normally.

If the Toolkit says the firmware is old or foreign, or MAKCU doesn't answer, go to Repair flash below. MAKCU's guide sends old v3 firmware that way too.

If an update starts and then stops, don't unplug anything. Check what the Toolkit says first, and send us the exact message in a ticket before you try again.

Old v3 firmware: Repair flash

Repair flash rewrites MAKCU's two chips one at a time. It's for v3, foreign firmware, or a MAKCU that won't answer after a replug, and it works even when the normal check can't read the firmware.

Give the normal check one more go first. Close other tools, unplug every cable for 10 seconds, plug in USB1 then USB2 with no button held, and leave USB3 empty. If the Toolkit reads the firmware now, use the normal update above.

Still nothing? Then:

1. On the Home screen, press MAKCU Toolkit · Repair flash at the top right.
2. The Toolkit looks for a repair package for your board. Press Repair flash, then Start. It backs up each chip before it erases it, so keep the backups in Documents\MAKCU backups and don't rename them.
3. Unplug MAKCU. Hold the small button next to USB1, plug USB1 into the PC running the Toolkit, then let go. Wait while it backs up and flashes.
4. When it asks, leave USB1 in and plug in USB2 as well, with no button held. Answer the USB2 question and wait for the check. Don't touch USB3 until the Toolkit asks.
5. When it tells you, unplug USB1 and USB2. Hold the button next to USB3, plug USB3 into the same PC, then let go. Wait for its backup and flash.
6. When both sides are done, unplug everything for 10 seconds. Plug USB1 and USB2 back in with no button held, leave USB3 empty and answer the question. Wait for Repair finished, then plug your mouse into USB3 and check it works.

Only change cables when the Toolkit asks. The buttons sit next to USB1 and USB3, so go by the printed labels. Our case has buttons over MAKCU's, so it can stay in the case.

If the Toolkit can't find a repair package

Check your internet and make sure you're on the current Toolkit. If it still can't, its Open migration page button opens MAKCU's web flasher at app.makcu.com/makcu. Close the Toolkit and any other serial tool before you connect there, then follow that page's steps. If you get stuck, open a ticket with the exact message.

After the update

• Check the speed.
  v4 runs at 4 Mbps by default, and your software has to use the same speed. If it needs 115200, hold the left (USB1) button for about a second and let go. Each hold switches it once. The driver and the port has the rest.
• Open your software again.
  Pick MAKCU's COM port in it like before.

Stress test

The Toolkit's Stress test checks MAKCU's input under load in about 40 seconds. You don't need it after a normal update. Run it when something feels off, or when we ask for it.

1. Close your software, games and anything important. Keep a second mouse plugged straight into the PC so you can stop the test.
2. Unplug every MAKCU cable and press Check unplugged.
3. Plug USB1 and USB2 both into the PC running the Toolkit, and the mouse you're testing into USB3. Press Scan connected devices and pick the mouse that goes through MAKCU, not your spare one.
4. Tick the box that allows small test movements and press Start stress test. Keep drawing circles with the mouse until it's done.
5. Under What happened to physical movement/buttons?, pick what really happened. Take a screenshot of the result for your ticket.

If it goes wrong

• No management port, or the connection check fails.
  Check USB2's cable goes into the PC running the Toolkit and carries data. Close other serial tools and makcu.com tabs, then do the full unplug and replug again.
• Old or foreign firmware, or still no answer.
  Use Repair flash. It opens even when the normal check fails.
• The update stopped.
  Leave the cables where they are and check what the Toolkit says before you try again.
• It can't reach the internet.
  Check your connection. The Toolkit needs it to download and check the firmware.

For any of these, open Diagnostics in the Toolkit. It asks you to plug your mouse straight into the PC for the scan, uploads a report to MAKCU and shows a device code like MK-XXXX-XXXX at the bottom. Open a ticket in our Discord (how to open one) with that code, what happened and the exact message.

Wiring and the COM port are in MAKCU setup, and MewTools' MAKCU error codes are in MAKCU and FERRUM errors.