Introduction

The CH340 line of chips is often found on microcontroller breakout boards and acts as the communication device between your computers USB to the microcontrollers serial.
Most computers will automatically have this driver installed although, for those who don't, this tutorial will take you through the steps required to get it installed and get your devices talking to each other
You may have either the CH340G or the CH340C variant of the chip. Both work in the same way and use the same drivers although the G variant requires a seperate external crystal oscillator for timing and the C variant uses an internal one

Required Materials

Depending on which board you have, the CH340 chip may be populated. Below are a number of boards we stock that use it

Arduino Mega 2560

Arduino Uno R3

Drivers

The driver works with both Windows, Mac and Linux based PCs. We've provided a quick link to the latest drivers below

• Windows EXE
• Windows (ZIP)
• Mac (ZIP)
• Linux (Zip)

Alternatively you can visit the manufacturers website and browse and download the drivers directly:

Installing on Windows

Download and run the executable

Click the UNINSTALL button to ensure any old drivers are cleaned. Then, click the INSTALL button.

Driver Verification

Theres a few ways to check if the driver installed properly so you dont spend hours scratching your head. Plug your CH340 based device into your computers USB port and follow one of the below checks

Option 1: Checking through device manager

After the driver is installed and your device is plugged in the CH340 should enumerate to a one of your computers COM ports

Open device manager by opening the Start Menu and typing Device Manager

After opening the device manager, expand the Ports (COM &LPT) tree section. The CH340 chip should show up as USB-SERIAL CH340 (COM##) where the ## will be a random number depending on your individal computer

Option 2: Checking through Arduino IDE

If you have the Arduino IDE installed you should be able to see a change in the number of COMs ports available with and without the CH340 device connected. Firstly, without the CH340 device connected to your computer, open Tools > Port and observe the number of Serial ports available

Next, connect the CH340 device to your computer and recheck the available serial ports. You should notice a new port that wasnt their previously, this is your new CH340 device connected and communicating with your computer

Installing on MAC

Open the terminal program by going to Go > Applications

Open the terminal program in Utilities > Terminal

You'll now need to point your terminal to where the *.kext files are stored

• For MAC OSX v10.8 and below, use the following command:

  cd /Library/Extensions
  

• For MAC OSX v10.8 and below, use the following command:

  cd /System/Library/Extensions
  

In this example we will be using a version higher than V10.9 so we will be using the first command

To check if the CH340 driver is in the correct path, use the following command to show the contents of the folder

ls

Now check for the CH340 driver files use the following command

ls | grep usb

You should see something that resembles the below. If you see either usb.kext or usbserial.kext), the CH340 driver is installed

If you found the above files in the path, we'll start by deleting them to prepare for installing the new drivers. Run the following commands to delete the drivers

sudo rm -rf /Library/Extensions/usb.kext
sudo rm -rf /Library/Extensions/usbserial.kext

Now its time to install the new driver. First download and extract the following driver:

Now, open the .pkg file in the unzipped folder and follow the instructions to install. You will need to restart your computer

Driver Verification

Use one of the following methods to verify if your driver has been successfully installed

Option 1: Through Command Line

With the CH340 device unplugged, open the terminal by going to Applications > Utilities > Terminal

Next, run the following command

ls /dev/cu* 

You will see a list of devices connected to your MAC. You should see something similar to the below

Connect the the CH340 device to your MAC and run the command again. You should see the CH340 device show up in the terminal. The device should show up as /dev/cu.wchusbserial*** the number will be different depending on your individual computer

Option 2: Through the Arduino IDE

If you have the Arduino IDE installed you should be able to see a change in the number of COMs ports available with and without the CH340 device connected. Firstly, without the CH340 device connected to your computer, open Tools > Port and observe the number of Serial ports available

Next, connect the CH340 device to your computer and recheck the available serial ports. You should notice a new port that wasnt their previously, this is your new CH340 device connected and communicating with your computer

Installing on Raspberry Pi (Raspbian)

Run the following commands in the terminal. After running, the latest CH34O drivers should be installed

sudo apt-get update
sudo apt-get upgrade

Installing on Linux

Download the CH340 linux Zip file with the following link

Driver Verification

Option 1: Through Command Line

Plug the device into your computer and run the following command

ls /dev/ttyUSB*

The port should show up as a result

Option 1: Through Arduino IDE

If you have the Arduino IDE installed you should be able to see a change in the number of COMs ports available with and without the CH340 device connected. Firstly, without the CH340 device connected to your computer, open Tools > Port and observe the number of Serial ports available

Next, connect the CH340 device to your computer and recheck the available serial ports. You should notice a new port that wasnt their previously, this is your new CH340 device connected and communicating with your computer