raspberry pi

1692 Articles

Putting The BBC In Seattle

January 13, 2013 by 57 Comments

radio

Among great British traditions, there’s tea, knowing how to lose an empire, tea, Parliament, big ben, tea, incalculable wit, Parliament, big ben, tea, and BBC radio. While Britons in foreign lands may not be able receive BBC radio over the airwaves, there is the remarkable BBC iPlayer that allows online streaming of all those awesome BBC radio stations. Unfortunately, moving away from the Prime Meridian means the BBC radio schedule deviates from the schedule ordained by divine right. In Seattle, for example, a Friday evening comedy would be broadcast in the middle of the afternoon. Basically, it’s like listening to  Prairie Home Companion on Saturday morning. It just feels wrong.

[Adam] came up with a clever solution to this problem. Yes, it’s really just a Raspberry Pi-powered web radio, but there’s a twist to this build: everything from BBC radio is buffered and time shifted. A program that airs at noon in London will now play on [Adam]’s radio at noon in Seattle.

The hardware portion of the build is an exceedingly British radio which [Adam] deftly modified to include an auxiliary input. The software portion of the build uses ffmpeg, mplayer, and a PHP script to stream the iPlayer audio to a file, wait 8 hours (or whatever the offset from GMT is), and start playing the audio.

In the end, the time shifted BBC radio works perfectly, and even caught the attention of a few people at BBC Radio 4. [Adam] was interviewed about his project, and was even able to listen to his interview several hours later.

Hardware SPI With Python On A Raspberry Pi

January 6, 2013 by 21 Comments

While the Raspberry Pi has very good support for an I2C bus, a lot of very cool chips – including the in system programmer for just about every ATtiny and ATmega microcontroller – use an SPI bus. [Louis] sent in a tutorial for getting hardware SPI on his Raspi, and even though it’s rather limited right now, it’s a step in the right direction.

Previously, [Brian Hensley] put up a tutorial for using the Linux SPI drivers with the Raspi. [Louis] wanted to play with SPI in Python, so he added a C extension to the spidev.c file (available here) that allows him to open an SPI connection, initialize, transfer, and close the connection.

After connecting an Arduino to the MOSI, MISO and SCK pins of his Arduino, [Louis] was able to transfer data from his Raspi over an SPI bus. It should be noted that a level shifter would be a really good idea here, but this is an excellent project if anyone would ever want to port AVRDude to Python.

 

Hackaday Links: Christmas Eve, 2012

December 24, 2012 by 9 Comments

It’s Christmas Eve, the perfect time to interact with your extended familial units, eat cookies, nog things up a little, and watch Die Hard. Christmas Eve also means it’s a low-effort day here at Hackaday, so here’s a few cool things we’ve run across in the past few weeks.

A Round OLED Display

1_13inch_Round_OLED

That right there is a circular OLED display. [ArtistEngineer] over on reddit found this display on AliBaba. It’s a 1.13 inch diameter display with a resolution of 128×128 (yeah, we don’t know either). This looks like a great display for a DIY wrist watch, digital gauge, or loads of other devices where a square display doesn’t make much sense.

There seems to be a few circular OLED display manufacturers – including Truly Semiconductors who happened to put up a datasheet for their round display – but sourcing these in reasonable quantities is a pain. Anyone up for a group buy? Think of the fun you’ll have coding a polar coordinate display!

Computing with transistors

gate

So you know computers are made up of simple logic gates, latches, buffers, and other miscellaneous digital cruft,  but how do we turn these digital circuits into a computer? Over the last few months, [Andrew] has been putting up a bunch of blog posts on the application of digital logic. Start out on the ‘Computing with Transistors’ post before moving on to The Digital State and Circuits and Arithmetic. There’s some good readin’ there.

 Embedding 3D objects in a web page

Go ahead. Click it. It’s Sketchfab that allows anyone to publish interactive 3D designs without a browser plugin. If anyone out there is trying to build a Thingiverse clone that isn’t tied to Makerbot, consider using this for the preview page for each object.

Surprisingly, Twinkies were the one thing that didn’t survive the Apocalypse.

twinkie

While there’s no use in mourning the death of the Twinkie – Little Debbie also makes small cream-filled cakes – you might as well include some Twinkies, Snowballs, Ding Dongs, and Ho-Hos in your Christmas baking. [scoochmaroo] on Instructables put together a list of homebrew recipes for the now defunct Hostess snack cakes.

Perfect for autonomous robots

code

[maxogden] over on the gits put together a script for automatically joining wireless networks on Linux. This was tested on a Raspberry Pi, and we’re thinking it would be perfect for whatever autonomous creation you’ll be building in your workshop next year.

FireHero: Raspberry Pi Controlled Pyrotechnics

December 22, 2012 by 24 Comments

Fire Hero 3

To put on a live pyrotechnic show at a music festival, [Chris] built the FireHero 3. The result is remotely controlled flames shooting up to 100 feet in the air.

The system is controlled by a Raspberry Pi and an Arduino. A server runs on the Pi and allows a remote computer to control the system. The Pi sends commands over serial to the Arduino, which switches solid state relays that actuate the valves.

There’s also some built in safety features: the system won’t boot unless you have the right key and RFID tag, and there are pressure transducers and temperature sensors to ensure the system is operating safely. A CO2 actuated valve can quickly stop fuel flow in an emergency.

Vaporized propane creates the fireballs. The vapor is created by heating the supply tank in a hot water bath. An accumulation tank stores the vapor and custom built manifolds distribute it to the various flame cannons. At each cannon, a silicon nitride hot surface igniter (HSI) is used to ignite the flames once the valve is opened.

After the break, watch a video the the FireHero making some flames.

Continue reading “FireHero: Raspberry Pi Controlled Pyrotechnics” →

Raspberry Pi Laptop Is Just A Little Too Big For A Pocket

December 21, 2012 by 30 Comments

Over on the Parts People blog, [Nathan] created his own Raspberry Pi laptop. It’s got all the bells and whistles, including a keyboard, trackpad, battery, and even a 3D printed case.

Of course [Nathan]’s laptop contains a Raspi, but the other included parts are where this palmtop computer is turned into something useful. For powering the Pi and 3.5″ composite LCD, [Nathan] took apart the battery pack from an old Dell laptop. By throwing out the bits of plastic surrounding these rechargeable cells and reusing the battery connector, [Nathan] was able to power the Pi, and all the peripherals for 10 hours.

Also included in [Nathan]’s Raspi palmtop is a 64 GB SSD connected to the powered USB hub. This, along with the 4 GB boot SD card, provides more than enough storage for listening to a music library, or even watching a few TV shows on the 3.5″ screen,

 

Manuel The Scottish Moose Speaks Your Tweets

December 19, 2012 by 10 Comments

tod1

The folks over at Torchbox needed a Christmas card this year. Previously, the most poplar holiday card was a web page that gave their visitors a chance to activate a ‘snow machine’ and spray confetti on a random employee, all while being streamed online. They wanted to replicate this bridge between virtual and real life interactions this year, and Manuel the talking moose was born.

Manuel needed a personality and interaction from random people on the Internet so the Torchbox team decided to make the fake moose head speak tweets in real-time with the help of a Raspberry Pi. The code running on the Raspi gets tweets with a #tbxmoose hashtag, sends that through a node.js script, and finally sent to the Festival speech synthesis system.

A few modifications needed to be done to Manuel before he was presented to the Internet. His jaw was chopped in half and a servo and animatronic controller were added for a proper presentation on Torchbox’s stream of Manuel’s random musings.

Raspberry Pi Hacking, Commando Style

December 12, 2012 by 36 Comments

raspberry-pi-and-notebook

If you’re lacking useful equipment for your Raspberry Pi hacking adventure, such as an HDMI monitor or power supply, this handy write-up will show you how to continue your hacking. All you’ll need is a laptop, the Raspberry Pi itself, an SD card, and an Ethernet and micro-USB cable. As noted in the article, it’s not really recommended to power the ‘Pi off of USB only, so this could potentially be a source of problems.

This hack begins by installing Linux on an SD card per this setup page, then using a Virtual Network Computing [VNC] setup to work with your Raspberry Pi. There are a few steps in between being able to do this, like setting up network sharing, and sleuthing out the IP address of the new processor, but everything is explained in detail for Mac and Linux. Windows users will have to do a bit of “sleuthing” of their own, but if you have some more information on this process, we’d love to hear about it in the comments!