Smart homes save energy right? Occupancy sensors turn off lights in vacant rooms, scenes and timers activate only the devices that are needed, only when they’re needed, and energy use feedback adjusts our behavior.

A comprehensive list of major Zigbee IC vendors and module makers, including a matrix of which module maker use which vendor's ICs.

After measuring the standby power consumption of various Zigbee and Z-Wave devices, I became curious about what efficiency regulations governed them. The EU has typically been at the forefront of energy use regulations, famously introducing the idea of a common charger back in 2009 before later mandating it, and issuing ecodesign requirements for transformers as early as 2009 (EC No 278/2009). Infact their first energy labelling directives were issued way back in in 1979.

How to configure an ATMega328p to consume lest than 1uA, while still retaining the ability to wake the processor up periodically via timer (or external interrupt).

Discussion of the design and implementations problems encountered during the design/construction of my in-wall Bluetooth audio player, with environmental sensors, proximity wake-up, metadata display, and cat animations.

Installation, power, and speaker connections for the custom made in-wall Bluetooth audio player. The wall plate connects to the speaker connections and power control electronics via a single RJ45 cable.

Firmware design for the Bluetooth audio player project. The basic architecture uses events to trigger external interrupts. Handlers post the event details into a queue and a simple control loop polls the queue and dispatches events to various handlers.

Mechanical design for the in-wall Bluetooth audio player project. The most difficult aspects of the design are mechanical. Fitting the module into a standard electrical junction box without visible fasteners, while allowing for it to be easily removed and look good is quite a challenge.

Circuit and PCB design for the Bluetooth audio player project. The circuit design is not complicated. The main sections are MCU with 8MHz crystal and supporting caps, ...

My latest project is a cat-themed Bluetooth audio player to be permanently installed in my bathroom. The unit will be housed in a standard electrical junction box on the bathroom wall..

STM32 microcontroller cheat sheet by product line, feature, model number. Includes product code descriptions and timer/peripheral information.

This is part 4 of a 4-part series on building a toaster reflow oven: Oven hardware Controller hardware Manufacturing Controller software Continuing on from the prior posts on the controller hardware and manufacturing, the device needs software.