Some days ago I posted about the RFM69 to MQTT gateway based on the ESP8266 I am working on. Over these days I’ve been fine tuning the gateway at the same time I was migrating one of my home sensors to Moteino: the Door Monitor. The previous version was based on an XBee radio and has been on duty for almost 3 years and a half. Real life battery time has been around 3 months for a CR2032 coin cell, which is not bad at all, but still…
Aside from using a Moteino and a RFM69 868MHz radio instead of the XBee, I have reduced the components list by moving hardware logic to software logic. This means using sleeping capabilities of both the ATMega328 and the RFM69 and coding in a clever way to reduce awake time.
Some weeks ago I received a parcel from Itead. Previously, I had written about the Sonoff and they were kind enough to send me two more of their home automation products for me to review: the S20 Smart Socket I wrote about two weeks ago and the Slampher.
The Slampher comes in a simple cardboard box with no documentation at all… just visit their wiki!
The Slampher is kind of a Sonoff RF that sits before any light bulb with an E27 screw. As you can see in the header pic of this post it adds quite some length to the group. It’s a bit bulky and might not fit in every lamp. Off course the board layout is different from the Sonoff and it uses a JST131U-800D 1A triac instead of a relay to switch the bulb. Aside from that they are equivalent.
Some 3 years ago I started building my own wireless sensor network at home. The technology I used at the moment has proven to be the right choice, mostly because it is flexible and modular.
MQTT is the keystone of the network. The publisher-subscriber pattern gives the flexibility to work on small, replaceable, simple components that can be attached or detached from the network at any moment. Over this time is has gone through some changes, like switching from a series of python daemons to Node-RED to manage persistence, notifications and reporting to several “cloud” services.
But MQTT talks TCP, which means you need some kind of translators for other “languages”. The picture below is from one of my firsts posts about my Home Monitoring System, and it shows some components I had working at the time.
All those gears in the image are those translators, sometimes called drivers, sometimes bridges, sometimes gateways. Most of them have been replaced by Node-RED nodes. But not all of them. This is the story of one of those gateways.
Firmware over-the-air (OTA) is great. It makes you shiver whenever you throw an update to one of your devices. The ArduinoOTA library for ESP8266 is so easy to use it’s almost magic. But once you have several devices deployed you start to think one step further.
Here I’m going to talk about two different options: writing an automated deployment script that performs OTA updates or giving your device the ability to call home querying for new updates, downloading them and flash itself into the latest version available.