Can't upload sketches to Arduino Nano clone with USB to serial chip ch340.

After installing drivers and plugging in, device has the name cu/tty.wch ch341 USB=>RS232 fa130 (with spaces), but Arduino can't recognize the full name (only tty.wch).

Is it possible to rename device in Mac OS or change device identifier?

UPDATE: ch340 new driver http://www.wch.cn/downloads.php?name=pro&proid=178

  • 2
    Found driver that works and after installing gives proper name for device. If you have WCH ch34x chip on arduino and get error "can't open device "/dev/tty.wch" or "/dev/cu.wch" in Arduino IDE, this should help goo.gl/EmN4IH (Dropbox)
    – Sonique
    Aug 10, 2014 at 4:15
  • I was going to suggest a symbolic link (e.g. in terminal ln -s /dev/tty.arduino "/dev/tty.wch ch341 USB=>RS232 fa130" but I tried it and it didn't work. Good you found a solution. Aug 10, 2014 at 6:12
  • I expect a symbolic link would work, but creating it may require admin permissions, and that complicated a name could require escaped characters. Aug 11, 2014 at 16:21
  • Does this work on El Capitan? The device disappeared after upgrade. Oct 24, 2015 at 15:32
  • Which version of OSX was this for? Jun 29, 2018 at 17:34

6 Answers 6


I used a terminal command:

sudo ln -s /dev/tty.wch\ ch341\ USB\=\>RS232\ 1450 /dev/tty.USB0

where /dev/tty.wch\ ch341\ USB\=\>RS232\ 1450 is the original name not recognized by Arduino; and /dev/tty.USB0 is the new port name.

  • You don't have to escape the spaces, rather, put everything in double quotes. Jul 20, 2015 at 21:45
  • The drawback is that after disconnecting the drive it also removes the symlink :-?
    – qwerty_so
    Oct 3, 2015 at 15:33

I am Antonis from codebender and we recently released drivers for the Mac.

If you want to overcome this problem, without disabling your computer's security settings, maybe I can help you with this! Codebender just released their Mac drivers package, which includes a new driver that supports the CH340G chip, on Yosemite and all other versions of OS X for Mac.

This will help you to install these drivers securely, and all you have to do is to download and install them.

You can find more information about the drivers in the codebender blog.

  • Can your driver be used by the regular Arduino IDE, or does it only work with Codebender? Oct 6, 2015 at 19:20
  • Loading codebender and its drivers (ch341 driver in particular) fixed my strange problem where only my old Arduino 1.05 IDE would work with my ch340 UNO and the the 2.0 (1.6.7) would not. Thanks. And it works in the browser as advertised.
    – Vicky T
    Feb 2, 2016 at 19:08
  • Worked very well for an unrecognized clone board ! Thanks
    – Jona
    Oct 11, 2016 at 14:23

I send email about this issue to WCH, and they change drivers to the latest version on their website, this is direct link http://www.wch.cn/downloads.php?name=pro&proid=178 (driver works and device has proper name in dev/)

  • Nice try. But actually the driver still creates that rotten name /dev/tty.wch ch341 USB=>RS232 fd130
    – qwerty_so
    Oct 3, 2015 at 15:32
  • 1
    Have to take back that comment. The new driver seemed to need some restart (log off/on) to activate and now creates /dev/tty.wchusbserialfd130. Cheers!
    – qwerty_so
    Oct 3, 2015 at 20:16

For Yosemite you seem to need to run this command in the Terminal and then restart the computer to get it to work.

sudo nvram boot-args="kext-dev-mode=1"
  • Can you explain what this does so us less smart people are not as scared running it.
    – user8452
    Apr 13, 2015 at 19:10
  • @ChristianJuth With this command, you enable non-approved drivers to work on newer OSX versions such as Yosemite.
    – Arda
    Apr 27, 2015 at 21:22

I was having the same problem. installed the latest drivers, I'm using yosemite, installed the Arduino IDE, and tried the board in windows 7 and it worked in windows, so board and cable are working.

In mac OS 10.10 in system report now they show as USB 2.0 Serial in arduino IDE it appears the port now (only after I used the SUDO command that sjunnesson posted) /dev/cu.wchusbserialalpha1310

so, use the sudo command if you are in yosemite


once you have installed the driver, you should be able to use it with any IDE or program

but I doubt anyone would prefer the Arduino IDE to codebender

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