Look, I’ve been there too. First the project just prints debug information for a human in nice descriptive strings that are easy to understand. Then some tool needs to log a sensor value so the simple debug messages gain structure. Now your debug messages {{look like : this}}. This is great until a second sensor is added that uses floats instead of ints. Now there are sprinklings of even more magic characters between the curly braces. A couple days later and things are starting to look Turing complete. At some point you look up and realize, “I need a messaging serialization strategy”. Well you’ve come to the right place! Continue reading “The Seedy World Of Message Serialization”→
Enshrined in the hacker hall of fame, the IM-Me was an instant messaging toy that turned out to be extremely hackable. You could easily ditch its instant messaging platform to turn it into a little spectrum analyser. Of course what’s old is new again, and in this age where we no longer have the Nokia 3110, the Sidekick, or even Blackberries, how shall we get our fix of those wireless gadgets with physical keyboards?
There are two versions of the device for hand and pocket, both of which come with QWERTY keyboards made with momentary-action switches, 18650 cell power, and LCD screens. The idea is that it could form a robust communication system when many others have failed.
As it stands they have a simple text messaging app in the firmware, but there are other features yet to come. Perhaps the most interesting is a possible store-and-forward meshing system in the future, which would make this a powerful comms tool in so many circumstances. Both of [Bobricius’] devices can be seen in the video below the break — no word from him on the possibility of a pink case option. Meanwhile [Bobricius] has appeared on these pages many times before. With so many to choose from it’s hard to pick one, but his Nixie-like LED display is quite memorable.
Today, nearly every modern consumer device wants to connect to the Internet for some reason. From your garage door opener to each individual smart bulb, the Internet of Things has arrived in full force. But the same can’t be said for most of our beloved conference badges. Wanting to explore the concept a bit, [Ayan Pahwa] set out to create his own MQTT-connected badge that he’s calling CloudBadge.
As this was more of a software experiment, all of the hardware is off-the-shelf. The badge itself is an Adafruit PyBadge, which doesn’t normally have any networking capabilities, but does feature a Feather-compatible header on the back. To that [Ayan] added a AirLift FeatherWing which allows him to use the ESP32 as a co-processor. He also added a strip of NeoPixel LEDs to the lanyard, though those could certainly be left off if you’re not looking to call quite so much attention to yourself.
The rest was just a matter of software. [Ayan] came up with some code that uses the combined hardware of the PyPadge and ESP32 to connect to Adafruit.io via MQTT. Once connected, the user is able to change the name that displays on the screen and the colors of the RGB LEDs through the cloud service. If you used something like this for an actual conference badge, the concept could easily be expanded to do things like flashing the badge’s LEDs when a talk the wearer wanted to see is about to start.
The modern conference badge has come a long way from simple blinking LEDs, offering challenges that you’ll likely still be working on long after the event wraps up. Concerns over security and the challenge of maintaining the necessary infrastructure during the event usually means they don’t include networking features, but projects like CloudBadge show the idea certainly has merit.
The elegance of Power over Ethernet (PoE) is that you can provide network connectivity and power over a single cable. Unfortunately not nearly enough hardware seems to support this capability, forcing intrepid hackers to take matters into their own hands. The latest in this line of single-cable creations is this beautiful Vacuum Fluorescent Display (VFD) clock from [Glen Akins].
Testing the VFD tube socket
One of the key advantages VFDs have over their Nixie predecessors is greatly reduced energy consumption, and after [Glen] ran the numbers, he saw that a display using six VFD tubes could easily be powered with standard PoE hardware. With this information, he started designing the PCB around the early 1990s era IV-12 tube, which has the advantage of being socketed so he could easily remove them later if necessary.
[Glen] first had to create a schematic and PCB footprint for the IV-12 tube that he could import into Eagle, which he was kind enough to share should anyone else be working with these particular tubes down the line. After a test of the newly designed socket was successful, he moved onto the rest of the electronics.
The clock is powered by a Microchip PIC18F67J60, which connects to the Ethernet network and pulls the current time down from NTP. After seeing so many clocks use an ESP to connect to the Internet over WiFi, there’s something refreshing about seeing a wired version. The tube segments are driven by a HV5812, also Microchip branded. Lastly, [Glen] used a number of DC/DC converters to generate the 1.5 V, 3.3 V, 5 V, and 25 V necessary to drive all the electronics and VFDs.
We absolutely love the simplicity of this clock, from its sleek aluminum enclosure to that single RJ45 jack on the back. But if you’re looking for something with a bit more flash, [Glen] also put together some PoE Christmas lights over the holidays which share a number of design elements with this project.
Back in 2018, [Paul-Louis Ageneau] created a 3D printed network-attached storage (NAS) enclosure for his Raspberry Pi. The design worked well, the Internet liked it when he posted the details on his blog, and all was right with the world. But of course, such glories are fleeting. Two years later that design needs updating, and thanks to the parametric nature of OpenSCAD, he’s been able to refresh his design for another tour of duty.
In our book, this is as much a cautionary tale as it is a success story. On one hand, it’s a testament to the power of CAD and desktop 3D printing. That a design can be tweaked and reproduced down the line with only minimal hassle is great for folks like us. But it’s also a shame that he didn’t get more than two years before some of the parts he used in the original NAS became unobtainium.
The main issue was that the integrated USB hub he used for the first version is no longer available, so the design had to be modified to accept a similar board. Unfortunately, the new hub is quite a bit wider than the old one. Resizing the entire case isn’t really an option since the Pi has to slide into it, so the hub now bumps out a bit on one side. He’s added a printable cover that cleans it up a bit, but the asymmetrical look might be a problem for some. While fiddling with the design, he also changed around the cooling setup so a larger fan could be mounted; now that the Raspberry Pi 4 is out, it can use all the cooling help it can get.
Addressable LEDs are a staple of homemade Christmas decorations in our community, as is microprocessor control of those LEDs. So at first sight [Glen Akins]’ LED decorated Christmas tree looks pretty enough, but isn’t particularly unusual. But after reading his write-up you’ll discover there’s far more to the project than meets the eye, and learn a lot about the technologies behind it that has relevance far beyond a festive light show.
The decoration is powered exclusively from power-over-Ethernet, with a PIC microcontroller translating Art-Net DMX-over-Ethernet packets into commands for the LED string. The control board is designed from the ground up and includes all the PoE circuitry, and the write-up gives a very thorough introduction to this power source that takes the reader way beyond regarding PoE as simply another off-the-shelf black box. Along the way we see all his code, as well as learn a few interesting tidbits such as the use of a pre-programmed EEPROM containing a unique MAC address.
So if your house has CAT5 wiring and you want an extra dimension to your festive splendour, you’ve officially got a whole year to build your own version. He’s featured here before, with his buzzer to break the Caps Lock habit.
We’re all used to the humble LED as a ubiquitous source of light, but how many of us are aware that these components can also be used as photodiodes? It’s something [Giovanni Blu Mitolo] takes us through as he demonstrates a simple data link using just a pair of LEDs and a couple of Arduinos. It’s a showing off his PJON networking layer, and while you’d need a bit more than a couple of LEDs on breadboards for a real-world application, we still think it’s a neat demonstration.
PJON itself is very much worth a look, being an implementation of a robust and error-tolerant network for Arduinos and other small microcontroller platforms. It has a variety of communication strategies for various different media, and as this LED demonstration shows, its strength is that it’s capable of working through media that other networks would balk at. Whether it’s controlling home automation through metal heating ducts or providing an alternative to LoRa at 433 MHz, it’s definitely worth a second look. We’ve mentioned it before, but remain surprised that we haven’t seen it more often since. Take a look, the video is below the break.
