Getting the Wemos D1 Mini board to work on Mac OS 10.13 (High Sierra)

Note: If you have recently upgraded to MacOS Mojave and are having issues getting your ESP* boards to work check out my post on fixing this common issue.

The title of this post is slightly misleading. The instructions below will allow you to program most of the ESP8266 and ESP32 boards. I am writing about the Wemos boards a they are the boards I use most.

The Wemos development boards are small, cheap, wifi ready micro-controllers. They have the ESP8266 wifi chips and (on the later models) have many GPIO pins broken out ready to use. They come pre-flashed with a Lua based firmware and while I understand that Lua is easy enough to pick up I wanted to be able to develop in the Arduino IDE.

The newer boards (see link above) come with a USB serial built in but some may require a USB TTL serial cable. This tutorial does not cover this.

These cheap boards are shipped with the CH3**G USB/serial chips. This is where the problem lies when getting these boards to work. These chips are not supported out of the box in most operating systems and so we have to install the drivers for them. Click here to download the drivers. If you had installed drivers before these will need to be removed. They can be found in `/System/Library/Extensions` and will have a `.kext` extension. Mine was called **usb.kext**. Yours may be different so check before blindly deleting it.

Once the driver has been installed the board should be available to use. Open terminal and type the following `ls /dev/tty*`. This will list all the available USB devices. You should see some like `/dev/tty.wchusbserial`.

To be able to program the NodeMCU board in the Arduino IDE you will need to add the board to the IDE. Copy the following URL *http://arduino.esp8266.com/stable/package_esp8266com_index.json*. Open the IDE and go to the files menu and click on preferences. Add the URL to the ‘Additional Boards Manager URL’.

Close the preferences panel and click tools. Under tools select boards and then board manager. Navigate to esp8266 by esp8266 community and install the software for Arduino.

Once this has been done you should be able to program the Wemos D1 mini board in the Arduino IDE.

Don’t forget that the Wemos D1 mini has a different pin layout to the Arduino boards. See the picture below to see how the pinouts compare.

The Wemos D1 mini board has been touted as an Arduino killer. And it is easy to see why. It is cheap, wifi enabled and easy to program. The majority of my project use this board and until something better comes along I will continue too.