A simple breadboard adaptor for the ESP-01 module.

A simple breadboard adaptor for the ESP-01 module.

Part 3 of a 3-part series on the new ESP8266 microcontroller

TheESP8266 is an interesting new WiFi-enabled microcontroller. We’ve already looked at the board and the talked about the new Arduino-compatible development environment that’s just been released and what it supports. Then we discuss how to install the environment and upload your first sketch onto the ESP-01 breakout board for the ESP8266 SoC. Now let’s see how to make a breadboard adapter for it.

While the ESP-01 is an excellent — and cheap — breakout board for the ESP8266 chip, it’s not a very convenient one to use when you’re breadboarding. So one of the first things I did when I got my bag of ESP-01 boards was design a breadboard adaptor for the breakout board, just to make my life a little easier.

Now this isn’t new, there are several other breadboard adaptors for the ESP-01 kicking around, however I decided to design mine so that it was plug and go — once you had your sketch loaded you could take the module away from the computer and just use a 5V supply. Everything else was onboard the board, so to speak.

Two ESP-01 modules breadboarded. The first (bottom) using an FTDI cable and 3.3V regulator. The second (top) using the custom breakout board.

Two ESP-01 modules breadboarded. The first (bottom) using an FTDI cable and 3.3V regulator. The second (top) using the custom breakout board.

The board I designed takes care of voltage regulation, smoothing the current out with some capacitors, and it has a nice bright LED to let me know that power is getting to places power should go. It also takes care of pulling the CH_PD pin high, and has a toggle switch to let me pull GPIO_0 low. Although sadly I still have to toggle the power to the board manually, maybe I’ll do something about that on the next board revision.

The ESP-01 sitting on top of the breadboard adaptor no longer connected to the computer, but with a USB power supply from the wall.

The ESP-01 sitting on top of the breadboard adaptor no longer connected to the computer, but with a USB power supply from the wall. The ESP-01 is associated with my WiFi network and I can now turn the LED on and off remotely.

The Bill of Materials for the adaptor is,

  • 1 × 0.1 μF capacitor
  • 1 × 10 μF capacitor
  • 1 × 220 Ω resistor
  • 1 × LED
  • 4 × 4-pin headers
  • 1 × SPDT switch
  • 1 × 3.3V regulator

and you can download the Gerber files from OSH Park, and order the boards at the same time if you feel inclined.

Why should I use the ESP8266?

While the ESP8266 can’t do everything you could do with an Arduino — for instance it only has one PWM pin that isn’t even exposed by the ESP-01 breakout board we’ve used here, you’d have to go looking for something like the Olimex board that Sandeep was using to get access to it — but for $5 it’s a bargain.

For $5 it doesn’t have to do the same amount as you can do with an Arduino, because at $5 you can afford to buy 5 or 6 of them for the price of a single Arduino board.

“This is inexpensive enough to be very much in the territory of ‘thousands of sensors-launched-out-of-a-cannon’-cheap.” — Brian Jepson

The ESP8266 was already well on its way to becoming — almost by stealth — one of the leading platforms for the Internet of Things. It’s super cheap, and super easy to work with, and it’s actually fairly easy — as such things go — to get your hands on, which makes a refreshing change.

However the arrival of Arduino compatibility is step change, suddenly the growing but still small community has opened their platform up to a much larger community. Suddenly there is a huge pool of people that  know how to work with the board, and I think we’re going to see an explosion of projects and products that otherwise wouldn’t get made. Because suddenly we have our hands on a WiFi board, that we all know how to use, that’s almost cheap enough to throw away.

Get out your soldering iron and buy some boards, I’d love to see what you build with it. Especially if it involves cannons.

This is the third part of three posts on the ESP8266 microcontroller.  The first part of the series introduces the board, while the second covers the installation of the new Arduino environment and building and uploading your first sketch to your ESP8266 board.