Low-energy ESP8266-based Board Sleeps Like A Log Until Triggered

November 13, 2018 by Brian Boucheron 32 Comments

Given the popularity of hacking and repurposing Amazon Dash buttons, there appears to be a real need amongst tinkerers for a simple “do something interesting on the internet when a button is pressed” device. If you have this need but don’t feel like fighting to bend a Dash device to your will, take a look at [Kevin Darrah]’s trigBoard instead.

The trigBoard is a battery-powered, ESP8266-based board that includes some clever circuitry to help it barely sip power (less than one microamp!) while waiting to be triggered by a digital input. This input could be a magnetic reed switch, push button, or similar, and you can configure the board for either normally open or normally closed switches.

The clever hardware bits that allow for such low power consumption are explained in [Kevin]’s YouTube video, which we’ve also embedded after the break. To summarize: the EPS8266 spends most of it’s time completely unpowered. A Texas Instruments TPL5111 power timer chip burns 35 nanoamps and wakes the ESP8266 up every hour to check on the battery. This chip also has a manual wake pin, and it’s this pin – along with more power-saving circuitry – that’s used to trigger actions based on the external input.

Apparently the microcontroller can somehow distinguish between being woken up for a battery check versus a button press, so you needn’t worry about accidentally sending yourself an alert every hour. The default firmware is set up to use Pushbullet to send notifications, but of course you could do anything an EPS8266 is capable of. The code is available on the project’s wiki page.

The board also includes a standard micro-JST connector for a LiPo battery, and can charge said battery through a micro-USB port. The trigBoard’s full schematic is on the wiki, and pre-built devices are available on Tindie.

[Kevin]’s hardware walkthrough video is embedded after the break.

Continue reading “Low-energy ESP8266-based Board Sleeps Like A Log Until Triggered” →

Advent Calendar Tracks The Days Until Christmas

November 12, 2018 by Steven Dufresne 2 Comments

What’s a hacker to do when Halloween’s over and a new source of ideas is needed for more hacks? Make something for Christmas of course. That’s what [Dario Breitenstein] did when he made his Advent calendar both as a decoration and to help instill some Christmas spirit.

Designed in SketchUp, it’s a WS2812 LED strip mounted in a clean looking walnut enclosure. The light diffuses through 3D-printed PETG lids with vinyl over them to outline the days. Naturally, it had to be Internet-connected and so an ESP8266 based WEMOS D1 mini board fetches the date and time from an NTP server. Sundays light up in red and Christmas Eve in purple.

This appears to be just the thing hackers like [vk2zay] could use for inspiration during their sort-of-annual Advent Calendar of Circuits wherein a different circuit is made each day leading up to Christmas.

ESP8266 Monitor Keeps An Eye On OctoPrint

November 5, 2018 by Tom Nardi 8 Comments

At this point, you’ve almost certainly heard of OctoPrint. The web-based control interface for 3D printers is especially popular for those who’s primary computers run on an operating system that has a penchant for occasionally imploding. Even if you aren’t laboring under that common software handicap, OctoPrint offers a wide away of compelling features. Perhaps chief among them the ability to monitor your printer over the network, and if you insist, over the Internet. But while OctoPrint provides the server side for getting your printer on the net, you’re on your own for the client.

Rather than using a web browser like some kind of peon, [David Payne] has come up with a very slick desktop OctoPrint monitor using the WeMos D1 Mini ESP8266 board. With an exceptionally low part count and housed in a (what else) 3D printed enclosure, this is a cheap and easy OctoPrint accessory that we suspect will be decorating many a hacker’s desk before too long.

The electronics are simple to the extreme, just hook the 4 wires of an 128×64 OLED I2C display to the appropriate pins of the ESP8266 board, and you’re ready to upload the Arduino code [David] has come up with.

His code is very polished, from using WiFiManager for initial network setup to providing its own web-based configuration menus to get the device linked up to your OctoPrint instance, [David] clearly wanted this to be as smooth an experience as possible for the end user. When the 3D printer isn’t working on a job, the monitor will even switch over to showing you the time and weather. We’ve seen commercial products that weren’t this user-friendly.

We also love the case design on this little gadget. While the aesthetics are perhaps debatable (sort of reminds us of the little fellows from Darwinia), we appreciate any functional print that doesn’t require supports. You’ll need to provide a couple of little screws to keep the back panel on, but other than that everything snaps into place.

Of course, you could always just use your smartphone to keep an eye on OctoPrint, and even if the remote management capabilities don’t grab your interest, there’s plenty of interesting plugins to keep you occupied.

Continue reading “ESP8266 Monitor Keeps An Eye On OctoPrint” →

Adding Energy Use And Cost To “Laundry Done” Notifications

November 3, 2018 by Donald Papp 29 Comments

Some time ago [Xose Pérez] got interested in generating a notification when his washer had completed a cycle, and now with added features like reporting power usage and cost, he’s put it all together into a Node-Red node that makes it easy to modify or integrate with other projects.

[Xose] started this journey with a Laundry Monitor he created that effectively used cheap hardware (and his own firmware) to monitor his washing machine’s current usage. That sensor was used as the basis for sending notifications informing him whenever the appliance’s cycle was done. Since then, he has continued to take household power monitoring seriously, and with a bit of added work can not only tell when a given appliance has been started and stopped, but can also summarize the energy usage and cost of the appliance, making the notifications more useful. The package is named node-red-contrib-power-monitor and is also hosted on GitHub.

Cheap WiFi-enabled smart switches are making it possible for even the dumbest of appliances to join the Internet of Things, so don’t ignore [Xose]’s complementary work on ESPurna, which is an alternative open-source firmware for a wide variety of ESP8266 and ESP8285 based smart switches, lights and sensors.

The Linux Throwie: Powering A Linux Server With A 0.3W Solar Panel

November 2, 2018 by Sean Boyce 63 Comments

Have you ever had one of those moments, when you’re rummaging through your spare parts heap, and have a rather bizarre project idea that you can’t quite get out of your head? You know, the ones that have no clear use, but simply demand to be born, of glass and steel and silicon?

This time, the stubborn idea in question was sort of like a solar-rechargeable LED throwie, but instead of a blinking light, it has a fully cloud-accessible embedded Linux server in the form of a Raspberry Pi 3 Model B+. Your choice of embedded Linux board should work — I just happen to have a lot of these due to a shipping error.

There were two main challenges here: First, it would have to combine the smallest practical combination of solar panel, power supply, and Li-ion cell that could run the Raspberry Pi. Second, we’ll need to remotely activate and access the Pi regardless of where it is, as well as be able to connect it to WiFi without direct physical access. In this article we’ll be dealing with the first set of problems — stay tuned for the rest.

Continue reading “The Linux Throwie: Powering A Linux Server With A 0.3W Solar Panel” →

Code Review Lamp Subtly Reminds You To Help Your Fellow Developer

November 1, 2018 by Donald Papp 10 Comments

[Dimitris Platis] works in an environment with a peer review process for accepting code changes. Code reviews generally are a good thing. One downside though, is that a lack of responsiveness from other developers can result in a big hit to team’s development speed. It isn’t that other developers are unwilling to do the reviews, it’s more that individuals are often absorbed in their own work and notification emails are easily missed. There is also a bit of a “tragedy of the commons” vibe to the situation, where it’s easy to feel that someone else will surely attend to the situation, but often no one does. To combat this, [Dimitris] built this Code Review Lamp, a subtle notification that aims to prod reviewers into action.

The lamp is based on a ring of RGB LEDs and a Wemos D1 Mini board. The Wemos utilizes the popular ESP8266, so it’s easy to develop for. The LED ring and Wemos are tied together with a slick custom PCB. Mounting the LED ring on the top of the PCB and the Wemos on the bottom allows for easy powering via a USB cable while directing light upward. The assembly is placed in a translucent 3D printed enclosure creating a pleasant diffuse light source.

Every developer gets a Code Review Lamp. The lamps automatically log in to the change management system to check whether anything is awaiting review. If a review is ready, the Lamp glows in a color specific to the individual developer. All this serves as a gentle but persistent reminder that someone’s work is being held up until a review is completed.

We love the way that the device has a clear purpose: it does its job without any unnecessary features or parts. It’s similar to this ESP8266 IoT Motion Sensor in that it has a single job to do, and focuses on it well.

Continue reading “Code Review Lamp Subtly Reminds You To Help Your Fellow Developer” →

Corporate Badgelife: Oracle’s Code Card

October 31, 2018 by Tom Nardi 30 Comments

We tend to think of elaborate electronic conference badges as something limited to the hacker scene, but it looks like the badgelife movement is starting to hit the big time. Now even the “big boys” are getting into the act, and pretty soon you won’t be able to go to a stuffy professional conference without seeing a sea of RGB LEDs firing off. We’ll let the good readers of Hackaday determine if this means it’s officially post-cool or not.

[Noel Portugal] writes in to tell us about how he created the “Code Card” during his tenure with the Oracle Groundbreakers Team. Featuring an ESP8266 and an e-ink screen, the Code Card serves not only as swanky way of identifying yourself, but as a real-world demonstration of physical devices pulling content from Oracle’s Cloud. Gotta keep those corporate overlords happy.

The Code Card is a fairly simple piece of hardware as far as badges go these days, but then the goal was never to be flashy. It does feature dual four-pin Grove System connectors on the backside though, so you can plug in additional sensors and gadgets for the customary badge hacking sessions.

To maximize runtime on the rechargeable coin cell battery, the Code Card only turns on the ESP after the user has pressed one of the buttons on the front. Once the ESP has finished performing whatever task the user requested, its powered back off completely rather than put into standby. Combined with the e-ink screen, power consumption while the device isn’t actively updating the display or pulling down new content is negligible.

[Noel] really went all-out on the software side, going as far as developing a web application which let conference attendees configure their Code Cards from their smartphones. Different functions could be assigned to short and long presses on the badge’s two buttons, and users could even select icons for the various functions from a list of images included in the firmware. A feature where attendees could upload their own images didn’t make the cut, but that surely won’t stop people from hacking around in the published Arduino source code and figuring out how to do it manually.

If you think the Code Card looks a bit familiar, it’s perhaps because it was designed in conjunction with Squarofumi, creators of the Badgy. So even if you aren’t hitting up any of Oracle’s upcoming conferences, you’re not completely out of luck if you want an e-ink badge to play with.