user3879: I bought a USB Nano V3.0 ATmega328 16M 5V Micro-controller CH340G board For Arduino and tried it with Arduino 1.6.6 on my MacBook Pro running OS X 10.11.1
The USB serial could not be seen. I searched on the web and found a few posts about this board, and downloaded http://www.wch.cn/download/CH341SER_MAC_ZIP.html
Most of the instructions were in Chinese, but the driver CH341SER_MAC.ZIP 资料类型：应用资料 资料大小：250KB 资料版本：1.1 更新时间：2013-12-25 seemed to install, but I cannot seem to find any /dev/tty and Arduino can't see any serial ports.
Has anyone had any success with this. (The seller has sold 18000 of these so someone may have got it working.)

user353: The CH340 is a chip with notoriously iffy driver support, definitely for OS X, and reportedly also for Windows. Some driver authors are not very fond of it, as evidenced by this affectionate comment
/*
 * driver for WinChipHead CH341/340, the worst USB-serial chip in the world.
 */

On the upside, the chip costs an order of magnitude less than the commonly used FTDI chips.
I've seen drivers from 3 sources:

The manufacturer drivers work off and on. The ones on the official site are not signed, and at some point, they started causing kernel panics for me.
The Codebender team is including free CH340 drivers in their installer, and I've had some success running those, although I'm having some difficulties with the latest version. YMMV.
So far, the drivers developed by Repleo have been rock solid for me. These are commercial, but, at less than $10, a pretty good deal in my opinion.


user26931: On MacOS Sierra it kept crashing the OS,  but version 1.3 works on MacOS Sierra.   
Found here:  https://github.com/adrianmihalko/ch340g-ch34g-ch34x-mac-os-x-driver

user3879: Using different search criteria I found http://kiguino.moos.io/2014/12/31/how-to-use-arduino-nano-mini-pro-with-CH340G-on-mac-osx-yosemite.html
This indicated a newer driver for OSX 10.9 and above at:-
http://kiguino.moos.io/downloads/CH34x_Install.zip
It is now working OK.
PS This was probably a Mac question, but I will answer as it is mainly of interest to Arduino users.
PPS The board worked on my Raspberry Pi which had the driver installed.
WARNING
The driver worked on OS X 10.11 but after upgrading to OS X 10.11.2 when I plug the USB cable into the Mac it causes a crash. This may or may not be related to the upgrade but after this happened twice I gave up.

3879: <p>I bought a <code>USB Nano V3.0 ATmega328 16M 5V Micro-controller CH340G board For Arduino</code> and tried it with Arduino 1.6.6 on my MacBook Pro running OS X 10.11.1</p>

<p>The USB serial could not be seen. I searched on the web and found a few posts about this board, and downloaded <a href="http://www.wch.cn/download/CH341SER_MAC_ZIP.html" rel="nofollow">http://www.wch.cn/download/CH341SER_MAC_ZIP.html</a></p>

<p>Most of the instructions were in Chinese, but the driver <code>CH341SER_MAC.ZIP 资料类型：应用资料 资料大小：250KB 资料版本：1.1 更新时间：2013-12-25</code> seemed to install, but I cannot seem to find any <code>/dev/tty</code> and Arduino can't see any serial ports.</p>

<p>Has anyone had any success with this. (The seller has sold 18000 of these so someone may have got it working.)</p>
 353: <p>The CH340 is a chip with notoriously iffy driver support, definitely for OS X, and reportedly also for Windows. Some driver authors are not very fond of it, as evidenced by this <a href="http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/dev/usb/uchcom.c?rev=1.13&amp;content-type=text/x-cvsweb-markup&amp;only_with_tag=MAIN" rel="nofollow">affectionate comment</a></p>

<pre><code>/*
 * driver for WinChipHead CH341/340, the worst USB-serial chip in the world.
 */
</code></pre>

<p>On the upside, the chip costs an order of magnitude less than the commonly used FTDI chips.</p>

<p>I've seen drivers from 3 sources:</p>

<ol>
<li>The manufacturer drivers work off and on. The ones on the official site are not signed, and at some point, they started causing kernel panics for me.</li>
<li>The <a href="https://codebender.cc" rel="nofollow">Codebender</a> team is including free CH340 drivers in their installer, and I've had some success running those, although I'm having some difficulties with the latest version. YMMV.</li>
<li>So far, the drivers developed by <a href="https://www.mac-usb-serial.com" rel="nofollow">Repleo</a> have been rock solid for me. These are commercial, but, at less than $10, a pretty good deal in my opinion.</li>
</ol>
 26931: <p>On MacOS Sierra it kept crashing the OS,  but version 1.3 works on MacOS Sierra.   </p>

<p>Found here:  <a href="https://github.com/adrianmihalko/ch340g-ch34g-ch34x-mac-os-x-driver" rel="nofollow">https://github.com/adrianmihalko/ch340g-ch34g-ch34x-mac-os-x-driver</a></p>
 3879: <p>Using different search criteria I found <a href="http://kiguino.moos.io/2014/12/31/how-to-use-arduino-nano-mini-pro-with-CH340G-on-mac-osx-yosemite.html" rel="nofollow">http://kiguino.moos.io/2014/12/31/how-to-use-arduino-nano-mini-pro-with-CH340G-on-mac-osx-yosemite.html</a></p>

<p>This indicated a newer driver for OSX 10.9 and above at:-
<a href="http://kiguino.moos.io/downloads/CH34x_Install.zip" rel="nofollow">http://kiguino.moos.io/downloads/CH34x_Install.zip</a></p>

<p>It is now working OK.</p>

<p>PS This was probably a Mac question, but I will answer as it is mainly of interest to Arduino users.</p>

<p>PPS The board worked on my Raspberry Pi which had the driver installed.</p>

<p>WARNING</p>

<h2>The driver worked on <code>OS X 10.11</code> but after upgrading to <code>OS X 10.11.2</code> when I plug the USB cable into the Mac it causes a crash. This may or may not be related to the upgrade but after this happened twice I gave up.</h2>
