Frustrated installing ch34x drivers on macbook running monterey

Hey! I just got an OMTech K40+ 40W CO2 laser engraver for my partner for the holidays. I’m not super familiar with macOS, but my partner’s laptop is a macbook pro running Monterey. The laptop has 4 ports that appear to be USB-c or similar; maybe some kind of thunderbolt, I don’t really know. The laser engraver only has a USB port.

I have a cable that is USB at one end and USB-c at the other end. I turned on the laser engraver (the test button on the engraver works – used it to burn a mark on tape to check mirror alignment; the air assist and vent fan are also running fine) and plug it in to the computer and launch LightBurn and I seem to be unable to connect to the laser.

All of the port options in LightBurn appear to be BlueTooth. When I go to the terminal and check /dev/, there’s nothing that says “usb” and all of the cu. and tty. entries are the BlueTooth options that I already saw in LightBurn.

I tried installing the CH34x driver for Mac; it says it installed successfully. When I check /library/extensions/ and /system/library/extensions/ (or whatever?), I see nothing that matches CH34x or anything that seems to have to do with USB. I also tried downloading and installing the virtual COM port drivers from VCP Drivers - FTDI. I’ve restarted a few times.

It looks to me like the drivers aren’t actually installed, despite the install appearing to happen successfully. Why can’t I see any USB ports in /dev/ or in LightBurn? What am I doing wrong?

Some people have found under similar circumstances that introducing a USB hub can get certain lasers to be detected. This is counter to general advice to remove all hubs from the equation.

So I didn’t think it could be the cable because the driver doesn’t seem to even exist in the /extensions/ directory – how do I make sure the drivers are even installed correctly?

This depends on the driver installed. In most likelihood if you’ve installed the driver and gotten a successful result the driver is likely to be there, but perhaps not with a name that you recognize.

Which specific driver did you install?

CH34xVCPDriver is the name of the file I used.

Can you post an About This mac picture

also, while connecting to your machine
Open a terminal
And type this command
ioreg -p IOUSB

post output
Repeat it rotating USBc cable 180º on the computer end.

Something you could try, if available too is a USB Dongle/Hub. to dumb down connection to USB 2.0

MacOs specially M1 chips are VERY very picky on usbC port usage and handshakes

Screenshot (hopefully) attached.

For the terminal command, here’s the output:
$ ioreg -p IOUSB
±o Root <class IORegistryEntry, id 0x100000100, retain 21>
±o AppleUSBVHCIBCE Root Hub Simulation@80000000 <class AppleUSBRootHubDevice, id 0x100000426, registered, matched, active, busy 0 (3 ms), retain 27>
±o Touch Bar Backlight@80700000 <class AppleUSBDevice, id 0x100000428, registered, matched, active, busy 0 (0 ms), retain 11>
±o Apple T2 Controller@80100000 <class AppleUSBDevice, id 0x10000042c, registered, matched, active, busy 0 (0 ms), retain 13>
±o Touch Bar Display@80600000 <class AppleUSBDevice, id 0x100000436, registered, matched, active, busy 0 (0 ms), retain 13>
±o FaceTime HD Camera (Built-in)@80200000 <class AppleUSBDevice, id 0x10000043a, registered, matched, active, busy 0 (0 ms), retain 13>
±o Ambient Light Sensor@80300000 <class AppleUSBDevice, id 0x10000043f, registered, matched, active, busy 0 (1 ms), retain 11>
±o Headset@80400000 <class AppleUSBDevice, id 0x100000444, registered, matched, active, busy 0 (1 ms), retain 11>
±o Apple Internal Keyboard / Trackpad@80500000 <class AppleUSBDevice, id 0x10001e844, registered, matched, active, busy 0 (36 ms), retain 21>

$ ioreg -p IOUSB
±o Root <class IORegistryEntry, id 0x100000100, retain 21>
±o AppleUSBVHCIBCE Root Hub Simulation@80000000 <class AppleUSBRootHubDevice, id 0x100000426, registered, matched, active, busy 0 (3 ms), retain 27>
±o Touch Bar Backlight@80700000 <class AppleUSBDevice, id 0x100000428, registered, matched, active, busy 0 (0 ms), retain 11>
±o Apple T2 Controller@80100000 <class AppleUSBDevice, id 0x10000042c, registered, matched, active, busy 0 (0 ms), retain 13>
±o Touch Bar Display@80600000 <class AppleUSBDevice, id 0x100000436, registered, matched, active, busy 0 (0 ms), retain 13>
±o FaceTime HD Camera (Built-in)@80200000 <class AppleUSBDevice, id 0x10000043a, registered, matched, active, busy 0 (0 ms), retain 13>
±o Ambient Light Sensor@80300000 <class AppleUSBDevice, id 0x10000043f, registered, matched, active, busy 0 (1 ms), retain 11>
±o Headset@80400000 <class AppleUSBDevice, id 0x100000444, registered, matched, active, busy 0 (1 ms), retain 11>
±o Apple Internal Keyboard / Trackpad@80500000 <class AppleUSBDevice, id 0x10001e844, registered, matched, active, busy 0 (36 ms), retain 21>

The second one is after flipping the cable 180 degrees (upside down, i guess). I tried again with a different port and a different cable and the output was identical to my eye.

Definitely not being detected

Must try
a) usb hub
b) different cable

It must be detected on terminal

Does Mac have a lsusb command?


I did find it… you have to install Homebrew, then you can install lsusb…

Much more easy on the eyes…

:smile_cat:

lsusb wouldn’t fix anything, just make it easier to see what’s what, yeah?

and a different cable or a hub would make the thunderbolt3 port appear in the list of usb devices?

Yes… the more tools you have to look at things … usually leads to a quicker diagnosis…

I have a Mac, but don’t use it much… I’m used to a Linux type OS… it’s similar… Had a G4 mac around the turn of the century… doesn’t seem much like what I had… I guess two plus decades…?

:smile_cat:

it worked! tried a USB hub and it immediately connected. Thanks!

Good news
In a way is really a matter or forcing the USB Handshake at 2.0 instead of 3.0
Pain but at times the simplest solution is the best :slight_smile:

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