Known-Good Hardware 🔗Or, making the case for dual testbeds. Breaking new ground 🔗When developing a new product, it often involves new hardware, electronics, and software. Every engineer loves to feast on new hardware, I think it triggers something deeply within. An urge to discover, perhaps. But the combination of so many new moving parts at the same time, makes it hard to understand where the problem is, when things don’t work as expected.

Buyers guide: toaster 🔗When the previous old toaster literally went up in flames, we needed a new one. The market for toasters seems to follow a bathtub-curve when it comes to price. There are a lot of really cheap ones, and quite many pretty expensive ones. Why so? Toasters are a solved problem since a century and the technology is simple and inexpensive. So one can assume the pricier ones are priced so mainly for the brand stamp.

Here follows a couple of tips on monitor use in Windows. Monitor brightness 🔗Edit Added in 2024. Windows seemingly have trouble with adjusting brightness on external monitors, hence the method below doesn’t work. Instead, there’s a utility called Twinkle Tray that handles this very well with a tray icon. I find myself often wanting to adjust the brightness of the monitor on the laptop, but since I’m using an external keyboard I have no access to those keys on the laptop.

ttag - Simple time tracking 🔗Since I’m working a lot in a CLI, and need to keep track of time and events, I’ve made this very simplistic time and event tracking utility. It’s based on a small script that appends a logfile. You need three things: a logfile path the ttag.sh-script adding alias-es to eg ~/.bashrc Logfile 🔗The logfile is just a text file. You need to determine the absolute path to it and add that to the ttag.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) Connected products need scheduled actions. Scheduled actions require time synchronized deceives. Here is we make that happen. In our daily lives, we are governed by time and schedules. We may wake up at 6:30 AM, take the bus at 7:34 AM, start work at 8:10 AM, pick up from school at 4:00 PM - based on synchronized and often fixed times of day.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) When the wireless mesh is unavailable, store data locally. A wireless mesh network reliably connects IoT (Internet of Things) devices, even in places where wireless is tricky. But even with a wireless mesh network, the IoT devices may become disconnected. We then need to store their data offline – and have them automatically post their data when they come back online.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) Every single Internet of Things (IoT) device needs an antenna. The antenna is crucial: it may make or break the communication with your devices. A good antenna will give you a good wireless range. A bad antenna may cause your devices to not even be reachable in the field. IoT devices are designed to be small, have a long wireless range, and have a long battery life.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) What is the range of my sub-GHz IoT device? Do the theoretical predictions of wireless range match the real world? We took a walk around the neighborhood to find out. The answer to this question isn’t always what the theoretical models tell us. We wanted to see for ourselves how much the theory might differ from the real world.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) Make them good looking, robust, functional, and sellable. At Thingsquare we use 3D printing for many of the IoT prototypes we build for customers. Here are the top 4 reasons why we do it, and why you should do it too: Hide the electronics Make it more functional Make it easier to sell Make it robust What is 3D Printing?

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) We recently got a new tool at Thingsquare, which helps us ensure that we have extremely low power consumption of our software: the Otii Arc current and voltage measurement box, by Qoitech. This little box quickly lets us – a bunch of software persons – measure and understand the power consumption of the software that we run on our low-power hardware.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) Inside each connected product is a piece of hardware. This hardware typically has to be custom designed for each product, but the level of customization varies depending on the product. Designing hardware for a Thingsquare-compatible product is straightforward because there are ready-made reference designs to use as a starting point. Behind every successful product is a successful hardware design.

(This is a repost of a blog post made for thingsquare.com, slightly edited to fit this format.) We have previously looked at how to make a wireless device live for years on one tiny coin cell battery. This time we up the game and make it live forever, using solar power and off-the-shelf hardware. We build a prototype of our device and go through the technical details involved in designing for solar power.

TLDR 🔗This tool converts SVG vector graphics to Cadsoft Eagle polygon. Get it here. Why 🔗Technology can even in its most raw and bare form certainly be beautiful. The bottom of a motherboard, with long, parallell, impedance-matched traces from PCI-connectors is a good example. A large BGA is another, with traces extending in every direction. I've long wanted to make my PCBs more beautiful, taking the few "colors" into full use.

HPDL-1414 clock 🔗After having ported Contiki to the Launchpad, I was eager on doing something with it. I built this simple clock with a vintage HPDL-1414 "smart four-character 16-segment alphanumeric" display and a msp430g2553. The soldered clock from above and bottom. There is a lot of solder flux residue, and lots of small black pieces of fabric from my bag, which lessens the appeal of the white solder mask. Quite nice though.

SimpleRDC 🔗This is a step forward in making wireless communication more easy and viable for extremely small systems. There already exist a number of protocols for low-power wireless. Most of them are quite complex and hence use much RAM and ROM which makes them unfeasible for the Launchpad and similarly constrained systems. This is a simple yet efficient radio duty-cycling protocol for Contiki that achieves 3% idle listening duty cycle while allowing for an average 65 ms latency with no prior contact or synchronization.