raspberry pi

1734 Articles

Code Craft: Cross Compiling For The Raspberry Pi

February 3, 2016 by 48 Comments

Sometimes there’s just no place like your desktop. You’ve already got your favorite development tools and references setup or installed and it’s a pain when you’re trying to work on an unfamiliar, or simply uncustomized, system. On your desktop everything is at your fingertips. If you want to search the web, the browser is just an alt-tab away. If you need a calculator, it’s right there to run. Your editor highlights syntax in your favorite colors already.

When developing on a Raspberry Pi, you leave all these creature comforts behind unless you spend the time to configure the Pi to your liking. Then it all gets wiped when you install a new distribution, like the recent change from Wheezy to Jessie. Even then it’s frustrating to switch back and forth between the desktop and the Pi because there is always something on the other system that you need. My usual comment is, “dirty word”, literally.

Cross-developing on your desktop is a very workable solution. We’re going to walk through setting up your desktop and a Pi to do this. This means loading a Pi ARM toolchain on your desktop and a debugging server on the Pi. This’ll let you develop and debug from in the comfort of your desktop. An added advantage is when you put that Pi in a robot you can debug over a wireless link.

Continue reading “Code Craft: Cross Compiling For The Raspberry Pi” →

Hackaday And Adafruit Launch The Pi Zero Contest

February 1, 2016 by 80 Comments

Hackaday and Adafruit are teaming up to bring you the Pi Zero Contest. Unless you’ve been hiding out in your workshop for the past month or so, you probably already know The Pi Zero is the $5 Linux-based computer which has been taking the world by storm. Think you have the next great project for this single-board computer? Enter it for a chance to take home one of three $100 gift certificates to the Hackaday Store. We know Zeros have been hard to find, so we’ll be giving away 10 of them before the contest is over. Even if you don’t have a Pi Zero, read on!

This is all about documenting quality projects to Hackaday.io. We’re looking for well thought out, well documented builds intended for the Pi Zero. Any project submitted to this contest can also be rolled over to the 2016 Hackaday Prize. Think of it as getting a head start.

Here are the details:

  • From February 2nd, to February 20th, Lady Ada will make 10 ‘From the Desk of Lady Ada’ broadcasts focusing on this contest. During each broadcast she will present an idea for a Pi Zero Project. You don’t have to build Lady Ada’s projects, they’re starter ideas to get your wheels turning. If you don’t have a Raspberry Pi Zero, don’t worry! You can prototype with a Raspberry Pi Model B, or a Pi 2. There are also 10 Pi Zero boards up for grabs before the contest is over.
  • The deadline for winning a Pi Zero is 12:00am PST February 25th, 2016. The judges will pick the 10 most well thought out and well documented projects.
  • On February 29th, the judges will announce the winners of 10 Raspberry Pi Zero boards.
  • The grand prize for this contest is one of three $100 gift cards to the Hackaday store. The deadline to enter is 12:00 am PST March 14th, 2016.

Entering is easy.  All you have to do is submit your project. Just click the “Submit to” drop down list on your project page. Then select Adafruit Pi Zero Contest.

So fire up your soldering irons, warm up your 3D printers, and load up your favorite code editor. It’s time to start hacking!

Hacking A Coffee Machine

January 28, 2016 by 19 Comments

The folks at Q42 write code, lots of it, and this implies the copious consumption of coffee. In more primitive times, an actual human person would measure how many cups were consumed and update a counter on their website once a day. That had to be fixed, obviously, so they hacked their coffee machine so it publishes the amount of coffee being consumed by itself. Their Jura coffee machine makes good coffee, but it wasn’t hacker friendly at all. No API, no documentation, non-standard serial port and encrypted EEPROM contents. It seems the manufacturer tried every trick to keep the hackers away — challenge accepted.

The folks at Q42 found details of the Jura encryption protocol from the internet, and then hooked up a Raspberry-Pi via serial UART to the Jura. Encryption consisted of taking each byte and breaking it up in to 4 bytes, with the data being loaded in bit positions 2 and 5 of each of the 4 bytes, which got OR’ed into 0x5B. To figure out where the counter data was stored by the machine in the EEPROM, they took a data dump of the contents, poured a shot of coffee, took another memory dump, and then compared the two.

Once they had this all figured out, the Raspberry-Pi was no longer required, and was replaced with the more appropriate Particle Photon. The Photon is put on a bread board and stuck with Velcro to the back of the coffee machine, with three wires connected to the serial port on the machine.

If you’d like to dig in to their code, checkout their GitHub repository. Seems the guys at Q42 love playing games too – check out 0h h1 and 0h n0.

Thanks [Max] for letting us know about this.

Old School Gauges Let You Know Which Way The Wind Blows

January 27, 2016 by 14 Comments

When your passion is a sport that depends on Mother Nature’s cooperation, you need to keep a close eye on weather conditions. With this in mind, and not one to let work distract him from an opportunity to play, [mechanicalsquid] decided to build a wind-monitoring gauge with an old-school look to let him know when the wind is right for kitesurfing.

old-school-meter-for-windBeing an aficionado of big engineering helped [mechanicalsquid] come up with a style for his gauge – big old dials and meters. We hesitate to apply the “steampunk” label to every project that retasks old technology, but it sure looks like a couple of the gauges he used could have been for steam, so the moniker probably fits here. Weather data for favorite kitesurfing and windsurfing locales is scraped from the web and applied to the gauges to indicates wind speed and direction. [mechanicalsquid] made a valiant effort to drive the voltmeter coil directly from the Raspberry Pi, but it was not to be. Servos proved inaccurate, so steppers do the job of moving the needles on both gauges. Check out the nicely detailed build log for this one, too.

For more weather station fun be sure to check out this meter-based weather station with a slightly more modern look. And for another build in the steampunk style, this vintage meter and Nixie power display is sure to impress.

Cricket Scoreboard Is A Big Win For Novice Hackers

January 24, 2016 by 14 Comments

The game of cricket boggles most Americans in the same way our football perplexes the rest of the world. We won’t even pretend to understand what a “wicket” or an “over” is, but apparently it’s important enough to keep track of that so an English cricket club decided to build their own electronic scoreboard for their – pitch? Field? Help us out here.

This scoreboard build was undertaken by what team member [Ian] refers to as some “middle-aged blokes from Gloucestershire” with no previous electronics experience. That’s tough enough to deal with, but add to it virtually no budget, a huge physical size for the board, exposure to the elements, and a publicly visible project where failure would be embarrassingly obvious, and this was indeed an intimidating project to even consider. Yet despite the handicaps, they came up with a great rig, with a laser-cut acrylic cover for a professional look. A Raspberry Pi runs the LED segments and allows WiFi connections from a laptop or phone in the stands. They’ve even recently upgraded to solar power for the system.

And we’ll toot our own horn here, since this build was inspired at least in part by a Hackaday post. The builders have a long list of other links that inspired or instructed them, and we think that says something powerful about the hacker community that we’ve all been building – a group with no previous experience manages a major build with the guidance of seasoned hackers. That’s something to feel good about.

Finally, A Power Meter Without Nixies

January 22, 2016 by 17 Comments

We’ve had quite a spate of home-brew energy meters on the tip line these days, and that probably reflects a deep inner desire that hackers seem to have to quantify their worlds. Functionally, these meters have all differed, but we’ve noticed a distinct stylistic trend toward the “Nixies and wood” look. Ironically, it is refreshing to see an energy meter with nothing but a spartan web interface for a change.

Clearly, [Tomasz Salwach] had raw data in mind as a design goal, and his Raspberry Pi-based meter delivers. After harvesting current sensing transformers from a bucket of defunct power meter PC boards, [Tomasz] calibrated them with a DIY oscilloscope and wired them and the voltage sensors up to an STM32 Nucleo development board. Data from the MCU goes to the Pi for processing and display as snazzy charts and GUI elements served internally. [Tomasz] was kind enough to include a link to his meter in his tip line post, but asked that we not share it publicly lest HaD readers love the Pi to death. But we can assure you that it works, and it’s kind of fun to peek in on the power usage of a house in Poland in real time.

It’s a nice project that does exactly what it set out to do. But if you missed the recent spate of Nixie-based displays, check out this front hallway meter or this one for a solar-power company CEO’s desk.