Raspberry Pi

1848 Articles

Thwomp Drops Brick On Retro Gaming

December 3, 2016 by 19 Comments

[Geeksmithing] wanted to respond to a challenge to build a USB hub using cement. Being a fan of Mario Brothers, a fitting homage is to build a retro-gaming console from cement to look just like your favorite Mario-crushing foe. With a Raspberry Pi Zero and a USB hub embedded in it, [Geeksmithing] brought the Mario universe character that’s a large cement block — the Thwomp — to life.

[Geeksmithing] went through five iterations before he arrived at one that worked properly. Initially, he tried using a 3D printed mold; the cement stuck to the plastic ruining the cement on the face. He then switched to using a mold in liquid rubber (after printing out a positive model of the Thwomp to use when creating the mold). But the foam board frame for the mold didn’t hold, so [Geeksmithing] added some wood to stabilize things. Unfortunately, the rubber stuck to both the foam board and the 3D model making it extremely difficult to get the model out.

Like [Han] in carbonite, that's a Rapsberry Pi Zero being encased in cement
Like [Han] in carbonite, that’s a Raspberry Pi Zero being encased in cement
Next up was regular silicone mold material. He didn’t have enough silicone rubber to cover the model, so he added some wood as filler to raise the level of the liquid. He also flipped the model over so that he’d at least get the face detail. He found some other silicone and used it to fill in the rest of the mold. Despite the different silicone, this mold worked. The duct tape he used to waterproof the Raspberry Pi, however, didn’t. He tried again, this time he used hot glue – a lot of hot glue! – to waterproof the Pi. This cast was better, and he was able to fire up the Pi, but after a couple of games his controller stopped working. He cracked open the cement to look at the Pi and realized that a small hole in the hot glue caused a leak that shorted out the USB port on the Pi. One last time, he thought, this time he used liquid electrical tape to waterproof the Pi.

The final casting worked and after painting, [Geeksmithing] had a finished cement Thwomp console that would play retro games. He missed the deadline for the USB Hub Challenge, but it’s still a great looking console, and his video has a lot of detail about what went wrong (and right) during his builds. There’s a great playlist on YouTube of the other entries in the challenge, check them out along with [Geeksmithing]’s video below!

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Running Intel TBB On A Raspberry Pi

December 1, 2016 by 17 Comments

The usefulness of Raspberry Pis seems almost limitless, with new applications being introduced daily and with no end in sight. But, as versatile as they are, it’s no secret that Raspberry Pis are still lacking in pure processing power. So, some serious optimization is needed to squeeze as much power out of the Raspberry Pi as possible when you’re working on processor-intensive projects.

This simplest way to accomplish this optimization, of course, is to simply reduce what’s running down to the essentials. For example, there’s no sense in running a GUI if your project doesn’t even use a display. Another strategy, however, is to ensure that you’re actually using all of the available processing power that the Raspberry Pi offers. In [sagiz’s] case, that meant using Intel’s open source Threading Building Blocks to achieve better parallelism in his OpenCV project.

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NixieBot Films Your Tweets

December 1, 2016 by 8 Comments

[Robin Bussell]’s NixieBot is a mash up of new age electronics and retro vintage components and he’s got a bunch of hacks crammed in there. It’s a Nixie tube clock which displays tweets, takes pictures of the display when it encounters tweets with a #NixieBotShowMe hash tag, and then posts requested pictures back to twitter. If a word is eight characters, it takes a snapshot. If it’s a longer message, NixieBot takes a series of pictures of each word, converts it to an animated GIF, and then posts the tweet. In between, it displays random tweets every twenty seconds. You can see the camera setup in the image below and you should check out the @nixiebot twitter feed to see some of the action.

nixiebot_05For the display, he’s using eight big vintage Burroughs B7971 Nixie Tubes. These aren’t easy to source, and current prices hover around $100 each if you can find them. The 170V DC needed to run each tube comes from a set of six 12V to 170V converter boards specifically designed to drive these tubes. Each board can drive at least a couple of nixies, so [Robin]’s able to use just four boards for the eight tubes. Each nixie is driven by its own “B7971 SmartSocket“, a dedicated PIC16F690 micro-controller board custom designed for the purpose. A serial protocol makes it easy to daisy-chain the SmartSockets to build multi character displays.

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Slack, Backwards Compatible With 1982

November 29, 2016 by 13 Comments

Slack is great, but there are a few small problems with the current implementations. There isn’t a client for Palm, there isn’t a client for the Newton, and there isn’t a client for the Commodore 64. The last of these severe oversights was recently fixed by [Jeff Harris]. He built a native Slack client in 6502 assembly for the Commodore 64.

When dealing with network applications and the C64, the first question that comes to mind is how to talk to the outside world. There are C64 NICs, and ESP dongles, but for this build [Jeff] turned to the C64 Userport. This card edge combination of a serial and parallel port allows the C64 to talk to anything with RS-232, and with a simple adapter, [Jeff] got his old computer talking to a Raspberry Pi connected to the Internet.

The C64 Slack client itself is written in 6502 assembly, and features everything you would expect. The Pi is required to talk to the Slack API, though, and uses a NodeJS app to translate the bits from the C64 to something the API can understand.

Does it work? Of course it does. Slack is just text, after all, and there doesn’t seem to be any PETSCII weirdness here. You can check out a video of the build in action below.

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Controlling Your Instruments From A Computer: Doing Something Useful

November 29, 2016 by 6 Comments

Do you know how to harvest data from your bench tools, like plotting bandwidth from your oscilloscope with a computer? It’s actually pretty easy. Many bench tools make this easy using a standard protocol with USB to make the connection.

In the previous installment of this article we talked about the National Instruments VISA (Virtual Instrument Software Archetecture) standard for communicating with your instruments from a computer, and introduced its Python wrapper with a simple demonstration using a Raspberry Pi. We’ll now build on that modest start by describing a more useful application for a Raspberry Pi and a digital oscilloscope; we’ll plot the bandwidth of an RF filter. We’ll assume that you’ve read the previous installment and have both Python and the required libraries on your machine. In our case the computer is a Raspberry Pi and the instrument is a Rigol DS1054z, but similar techniques could be employed with other computers and instruments.

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Controlling A Game Room With Amazon Echo

November 27, 2016 by 2 Comments

If there are two things we love here at Hackaday, it’s games and automating mundane tasks by adding a lot of electronics and voice control. A game room is, therefore, the perfect sandbox for projects that get us excited in all of the right ways. Liberty Games, a UK-based games room company, already had a really impressive game room (as you might expect). They’ve just posted an awesome build log showcasing how they went about automating mundane game room tasks by adding a lot of electronics and voice control.

There were four tasks that Liberty Games wanted to be able to complete with voice control: releasing billiards balls on their pool table, adding credits to an arcade machine, releasing pinballs on a pinball machine, and control of a CD jukebox. For all of these tasks, they used an Amazon Echo, which already has built-in support for adding new “skills” (Amazon’s term for user-created Alexa commands). These skills allow the Echo to communicate with other devices using JavaScript Object Notation (JSON).

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DIYing A Raspberry Pi Power Bank

November 26, 2016 by 25 Comments

Over the last decade or so, battery technology has improved massively. While those lithium cells have enabled thin, powerful smartphones and quadcopters, [patrick] thought it would be a good idea to do something a little simpler. He built a USB power bank with an 18650 cell. While it would be easier to simply buy a USB power bank, that’s not really the point, is it?

This project is the follow-up to one of [patrick]’s earlier projects, a battery backup for the Raspberry Pi. This earlier project used an 14500 cell and an MSP430 microcontroller to shut the Pi down gracefully when the battery was nearing depletion.

While the original project worked well with the low power consumption Pi Model A and Pi Zero, it struggled with UPS duties on the higher power Pi 3. [patrick] upgraded the cell and changed the electronics to provide enough current to keep a high-power Pi on even at 100% CPU load.

The end result is a USB power bank that’s able to keep a Raspberry Pi alive for a few hours and stays relatively cool.