Hi all, and welcome to the first installment of Hackenings, our review/preview of the week in global hackerspaces. If you’d like to get the news out about upcoming events at your space, get us an e-mail before Thursday to get it published on Saturday. If you’d just like to brag, any time is fine. Drop us a line at tips@hackaday.com and put [Hackenings] in the subject to make sure that we see it.
This week we’ve got two stories of hackerspaces on the move, but they couldn’t be more different. The Burbank Makerspace has upgraded to fancier new digs, while Cairo Makerspace‘s building collapsed, and now they’re taking their show on the road with a hackerspace-in-a-van.
[ttsiodras] tells an epic tale of getting a custom Debian kernel installed on an Asus MemoPAD (ME103K) tablet. Skipping to the end of the saga, he discovers what looks like serial data coming out on the headphone jack when the system boots, but the signal was so distorted that he couldn’t simply interpret it. The solution turns out to be attaching a level-converter chip.
A level converter is a non-inverting amplifier, usually with a Schmitt trigger for immunity against noise. In this case, it acts like a “binarizer” — outputting a high voltage when the input rises above a threshold, and a low when it drops below. It’s the right part when you need to clean up a messy digital signal, and in this case works just fine because the capacitive distortion effects slow down both the leading and trailing edges of the signal, keeping the serial data’s timing intact.
That was the spoiler. If you want to read up on putting a custom Linux on an Android device, check out [ttsiodras]’s first post where he backs the machine up, and the second where he gets his custom kernel up and running. If you’re ever faced with an Android tablet that hasn’t been owned yet, or if you just have a DIY streak, this should help you get started.
Using the audio jack for serial is actually not uncommon, and discovering a serial terminal that listens at boot time is our favorite way to wedge a Linux OS into odd devices. So when you see a funny, distorted signal coming out at 115,200 baud, take a moment to clean its edges up and see what you’ve got.
Modern monitors with an HDMI input connect right up to the Pi. Before HDMI came VGA, but the Pi doesn’t do that natively. One solution is to use a composite-to-VGA converter and pull the composite signal out of the audio jack. Lacking the right 4-pole audio cable, [TPAI] soldered some RCA plugs directly onto the Pi, and plugged that into the converter. On a yet-older monitor, he faced a SCART adapter. If you’re European, you’ll know these — it’s just composite video with a different connector. Good thing he had a composite video signal already on hand.
The pièce de resistance, though, was attaching the Pi to his 1980 Vega TV set. It only had an antenna-in connector, so he needed an RF modulator. With a (presumably) infinite supply of junk VCRs on hand, he pulled an upconverter out of the pile, and got the Pi working with the snazzy retro TV.
Yes, yes. We all love to laugh at a technology in its infancy. It’s like when robots fall down: it’s a cheap shot and things will surely get better, right? Indeed, the Guardian has had its fun with this particular WiFi kettle before — they’re British and nothing is more important than a remote-controlled cuppa.
Every time we hear about one walled-garden protocol not speaking to another, and the resulting configuration mayhem that ensues, we can’t help think that [Mike] was right: home automation has a software problem. But that’s putting the blame on the technology. (We’re sure that [Mark] could have made the kettle work if he’d just applied a little Wireshark.)
There’s another mismatch here — one of expectations about the users. A water kettle is an object that should be usable by grandmothers, and a complex networked device is clearly aimed at techies and early adopters. Combining the two is asking for trouble. Non-functioning IoT devices are the blinking 12:00 of our generation.
What do you think? Where’s the blame here? Poor design, bad software stack, stupid users, or failure of mega-corps to integrate their systems together? More importantly, how could we make it better?
Nobody’s perfect. Sometimes you’re up late at night writing a blog post and you stumble upon an incredible story. You write it up, and it ends up being, well, incredible. IEEE Spectrum took the bait on this video (embedded below) where [Keran McKenzie] claims to have built a self-driving car for under $1,000 AUS with Arduinos.
The video is actually pretty funny, and we don’t think it’s intended to be a mass-media hoax as much as a YouTube joke. After letting the car “take over” for a few seconds, it swerves and [Keran] pretends to have hit something. (He’s using his knees people!) There are lots of takes with him under the car, and pointing at a single wire that supposedly makes the whole thing work. Yeah, right.
[Mathieu] wrote in with his laser target practice game. It’s not the most amazing hack in the history of hackery, but it’s an excellent example of the type of simple and fun things you can do with just a little bit of microcontrollering.
First off, the gun is a broken toy gun that used to shoot something other than red collimated light beams. The Arduino knockoff inside reacts to a trigger pull and fires the laser for around 200 milliseconds. The gun also has a “gas gauge” that fills up with repeated shots and cools down over time. And therein lies the game — a simple race to ten, where each player only has a fixed number of shots over time.
The targets are simply a light sensor, scorekeeping LED display, and a buzzer that builds tension by beeping at you as the countdown timer ticks down. The bodies are made out of 3D-printed corners that connect some of [Mathieu]’s excess wooden goat-cheese lids.
All the code is up on GitHub so you can make your own with stuff that you’ve got lying around the house. The “gun” can be anything that you can embed a laser in that makes it aimable. Good clean fun!
Getting kids interested in programming is all the rage right now, and the UK is certainly taking pole position with its BBC micro:bit, just recently distributed to every seventh-grader in the land. Germany, proud of its education system and technological prowess, is caught playing catch-up. Until now.
The Calliope Mini (translated here) is essentially a micro:bit clone, but one that has learned from the experience of its spiritual forefather — the connection points are spread around the outside of the board where the crocodile clips won’t accidentally touch each other.
Not content to simply copy, the Calliope also adds additional functionality. A microphone and speaker are integrated onboard, as is a Grove-style I2C connector. They’ve even added a TI DRV8837 H-bridge motor driver, so students could make a rolling robot straight out of the box.
