Just picked up one of these neat ePaper displays from AliExpress for $9.90 for the esp8266. It’s 2.13" in diagonal, has a resolution of 250x122 and is made by Lolin. Lolin produce a whole bunch of quality esp8266 items - including the ubiquitous Wemos D1 Mini and various I2C sensors. It’s not a shield …

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A minor annoyance, but one that plagues me: when you put a wash on, forget about it finishing, only to discover the damp washing hours later festering in the washing machine. There’s only one thing to it - a massively overengineered smart home solution! Sonoff POW This is a smart device that can be had from …

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Problem: a recipe calls for 250ml double cream (48% fat) and 100ml whole milk (3.5% fat). I only have double cream (48% fat) and semi-skimmed milk (1.5% fat). How much do I adjust the double cream by to get the same quantity liquid and fat content? It’s a simple simultaneous equation, so solving it with Sympy is …

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This is part 1 of 2 about using Elasticsearch and Kibana to track patterns in baby activity. Part 2 is on elastic.co. Kicking things off According to countthekicks.org “Counting baby kicks is important because changes in your baby’s movement pattern may indicate potential problems with your pregnancy”. …

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I struggled getting the Yale Conexis smart lock working with the Aeotec Z-Stick Gen5. Turns out the issue is it must be a secure pairing - the default method in the instructions (unplug Z-Stick, press button near to the device, initiate pairing), does not perform a secure pairing, and so even though the device will …

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The new Raspberry Pi Zero W is the perfect pairing to go with the Xiaomi Mi Flora. The Flora is a bluetooth stick you push into the soil next to a plant and can be polled over Bluetooth LE for the sensor data - soil moisture, temperature, light and soil conductivity. Part list Raspberry Pi Zero W. I used Pimoroni …

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Bluetooth doesn’t work out the box for Archlinux but thankfully a helpful user has created packages to support the Pi 3 which also work on the Zero W (see forum post). There’s a couple of caveats to getting them working I’ll step through. First install bluez and bluez-utils older than 5.44 - you must …

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This project was to build a simple garage security system to alert of intruder access to the garage by notification over Wifi. Parts list Wemos D1 mini & mini protoboard The esp8266 is the workhorse of any project - it monitors the sensors and sends notifications over Wifi. I used the Arduino system with Platformio …

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The Amazon Dash is a Wifi button originally intended for the ultra- lazy for reordering consumables from Amazon when you’re running low. It was going to £1 recently in Black Friday promotions, so I thought I’d have to snap one up. Normally they go for a not bank breaking £5, which you can recoup if you …

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CheerLights is an “Internet of Things” project created by Hans Scharler where people volunteer to synchronise their lights all across the world to one colour. In a truly democratic fashion, the colour changes by anyone sending a tweet with a colour #cheerlights. Check out twitter to see it live: #cheerlights. I …

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