1btn is a Battery Powered Open Source ESP8266 WiFi Button

If you have some WiFi power switch like Sonoff TH16 at home, you’d normally control them using a mobile app or a web interface. This is all good, but getting your phone, unlocking it, and launching the app to turn on or off an appliance is not the most efficient way to operate, and in some cases, some people in the household may not know how to use a smartphone. Physical WiFi buttons are the solution, but there aren’t so many for sale. We’ve seen previously it was possible to hack an Amazon Dash, but it’s not really that flexible, and 1btn could potentially be a better option, as it’s open source and based on Espressif ESP8266 WiSoC. 1btn specifications: WiFi Module – ESP-12F based on Espressif ESP8266 MCU – Microchip Atmel ATmegaxx8 AVR MCU Connectivity – 802.11 b/g/b WiFi up to ~50 meter range USB – 1x USB port for charging and programming (via on-board USB to Serial chip) […]

Karl’s Home Automation Project – Part 4: MQTT Bridge Updated to Use YS-IRTM IR Receiver & Transmitter with NodeMCU

In a previous article, I wrote about an MQTT bridge by 1technophile. I added a DHT temperature and humidity sensor as well as a light sensor. Previously it included a software decoder to decode the IR signal. I never did test the IR transmitter on the gateway, as I didn’t have the parts. But thanks to IC Station, who sent me over a small YS-IRTM hardware based decoder and NodeMCU that I am writing about today. I have replaced the software based version with the YS-IRTM module in the latest update. I found this project challenging. I admit I am a little weak in my programming skills. It was difficult to find documentation but I found a forum talking about this device and basics of how it works. When an IR code is recognized it sends 3 hex codes via serial connection on the transmit pin. To transmit, it expects 5 hex codes: A1,F1,xx,xx,xx. A1,F1 tells it to send the […]

Is NodeMCU ESP-32S Board Now Selling for $8.50 Shipped?

ESP32 SoC with WiFi and Bluetooth launched last September for around $3, followed soon after by ESP32 modules for $7, and a few weeks later, easier to use ESP32 development boards were introduced, but sold for around $20 likely due a mismatch between supply and demand. That’s not overly expensive, but in a world of $4 ESP8266 boards and $10 Raspberry Pi Zero W with Linux, WiFi and Bluetooth, it may feel that way. But today, I noticed DealExtreme sold GeekWorm ESP32 board with ESP-WROOM-32 module for just $11.64 shipped. That’s good progress, but surely Aliexpress must now have cheaper options, and sure enough, I could find NodeMCU ESP-32S board (now confirmed NOT to be an official NodeMCU devkit) sold for $6.95 + shipping, which brought the price up to about $8.50. NodeMCU ESP-32S specifications: Wireless Module – ESP-WROOM-32 with Espressig ESP32 dual core processor with 802.11 b/g/n WiFi and Bluetooth 4.0 LE Expansion – 2x 19 pin headers with […]

Secure IoT Connectivity with NodeMCU ESP8266 Board, ATECC508A Crypto Chip, Mongoose OS, and AWS IoT

There are many examples of Internet of Things projects, but more often than not the implementation is not secure, either because the device is exposed to the Internet with minimum or no security (worst case), or a gateway (hopefully) provides secure connection to the Internet, but the communication between sensor nodes and the gateway in the local network is not secure, due to memory limitation of the nodes, for example it might be challenging to implement security on ESP8266. Mongoose OS is an open source operating system for the Internet of Things developed by Cesanta working on ESP32, ESP8266, STM32, and TI CC3200, and the developers have demonstrated a secure solution with Mongoose OS running on ESP8266 connecting over a TLS connection to AWS IoT (Amazon Web Service IoT) and using TLS credentials stored in Microchip ATECC508A CryptoAuthentication Device. The addition of ATECC508 chip either using “XplainedPro extension board for crypto products” (ATCRYPTOAUTH-XPRO) or ATECC508A chip itself, is to avoid […]

Karl’s Home Automation Project – Part 2: 433 MHz / WiFi MQTT Bridge, Door & PIR Motion Sensors

Karl here again for part 2 of my home automation project. We will be looking at how to automate your lights based on time of day and motion. In the first part we setup Home Assistant and uploaded firmware to basic Sonoff Wifi switches. Today we will setup a 433 MHz to MQTT bridge and some sensors. 433 MHz Depending on your country 433 MHz is an open frequency to use to communicate with. There are hundreds of different types of devices that use 433 MHz to communicate information. We will be focusing on 2 today from Gearbest: WMS07 motion sensor (left) and WDS07 door/window sensor (2 parts, right). I am not taking the door/window sensor apart, since it is super basic, but I’ve included some photos of the PIR motion detector. 433 MHz Bridge While contemplating how to get presence on a per room basis I ran across this project. It monitors 433 MHz signals and publishes it to […]

$10 RTLDuino is an Arduino Compatible WiFi IoT Board based on Realtek RTL8710AF WiSoC

Last summer, we discovered a cheap RTL8710AF WiFi module with many of the same function as ESP8266, but with an ARM Cortex M3 core instead. The only problem is that it was not quite as easy to play with as ESP8266 boards, as at the time I started by playing with AT commands with B&T RTL00 RTL8710AF module, and later on, I got a more convenient PADI IoT Stamp with breakout board, but if you wanted to change the firmware you had to play with the SDK and a J-Link SWD debugger. Realtek RTL8710AF did not offer the convenience of Arduino IDE program like its big brother “RTL8195AM” from the same Ameba family. I know mbed is being worked on, but in the meantime things have changed for the better, as kissste informed me that RtlDuino implementation added Arduino support to RTL8710AF and RTL8711AM modules, and an NodeMCU-like board with the same name was also sold for less than $10 […]

ESP32 Updates – ESP32-S Module Replaces ESP3212, ESP32 DevBoards for Sale, Arduino & NodeMCU Support

There have been some developments with regards to Espressif ESP32 in the last month since my post about upcoming ESP32 development boards. First ESP3212 module is no more, and has been replaced with ESP32-S module with about the same features, but it’s not pin-to-pin compatible, so the new module won’t work with older breakout boards made for ESP3212. ESP32-S is now out of stock on Seeed Studio, but you’ll find it on IC Station, Banggood, and others shops. One good news is that it’s now easier to buy – or at least pre-order – ESP32 development boards, although stock may still be an issue, as the platform is very popular. If you live in the US, you can now backorder “Sparkfun ESP32 Thing” for $19.95. ESP32 board can be powered by either a micro USB power supply or a LiPo battery, and exposes close to 30 I/O pins. ESP32 developer board is still listed on Adafruit for $15, but you […]

Some ESP32 Development Boards to Look Out For: NodeMCU, Widora-air, Nano32, Noduino Quantum, and Wemos

Espressif ESP32 WiFi + BLE SoC launched at the very beginning of the month, shortly followed by ESP3212 module, and while Adafruit sold a few breadboard-friendly ESP32 development boards to developers for $15 a few days ago, stock was limited, and it’s not possible to easily purchase ESP32 boards today, and that’s OK because firmware and software support is still in progress. Several companies are working on such ESP32 boards however, and they tend to show the development progress on social networks, so I thought it would be fun to look at what’s coming… Amica (NodeMCU) ESP32 Board The current NodeMCU board is one of the most popular ESP8266 development platform, and that’s not surprising they are working on an ESP32 version. I don’t have pictures nor full  specs of the board yet, but the company showcased their early work on ESP32 last June. Widora-air I only discovered Widora recently via their NEO WiFi board running OpenWrt, but they are […]