raspberry pi

1701 Articles

This Hacker Fit An Entire RetroPie In An Altoids Tin

April 23, 2017 by 29 Comments

A few months ago, [wermy] built the mintyPi, a Raspberry Pi-based gaming console that fits inside an Altoids tin. It’s amazing — there’s a composite LCD, an audio DAC, and a chopped up Nintendo controller all connected to a Raspberry Pi for vintage gaming goodness on the road. Now, there’s a new mintyPi. The mintyPi 2.0 vastly improves over the earlier generation of this groundbreaking mint-based gaming console with a better screen, better buttons, customized 3D printed bezels, and better audio. Truly, we live in a Golden Age.

Version two of mintyPi uses 3D printed parts and includes a real hinge to keep the display propped up when the Altoids tin is open. Instead of a DAC-based audio solution, [wermy] is using a USB sound card for clearer, crisper sound. This version also uses the new, wireless version of the Raspberry Pi Zero. The Raspberry Pi Zero W allows this Altoids tin to connect to the Internet or, alternatively, gives the user the ability to dump ROMs on this thing without having to connect it to a computer.

For the software, this retro Altoids video game machine is running RetroPie, a very popular way to get retro video games running under low-power Linux machines. Everything is in there, from the NES to Amstrad to the Sega Master system.

Right now, there aren’t a whole lot of details on how [wermy] created the mintyPi 2.0, but he promises a guide soon. Until then, we’ll just have to drool over the video embedded below.

Continue reading “This Hacker Fit An Entire RetroPie In An Altoids Tin” →

The Raspberry Pi As An IR To WiFi Bridge

April 23, 2017 by 28 Comments

[Jason] has a Sonos home sound system, with a bunch of speakers connected via WiFi. [Jason] also has a universal remote designed and manufactured in a universe where WiFi doesn’t exist. The Sonos can not be controlled via infrared. There’s an obvious problem here, but luckily tiny Linux computers with WiFi cost $10, and IR receivers cost $2. The result is an IR to WiFi bridge to control all those ‘smart’ home audio solutions.

The only thing [Jason] needed to control his Sonos from a universal remote is an IR receiver and a Raspberry Pi Zero W. The circuit is simple – just connect the power and ground of the IR receiver to the Pi, and plug the third pin of the receiver into a GPIO pin. The new, fancy official Raspberry Pi Zero enclosure is perfect for this build, allowing a little IR-transparent piece of epoxy poking out of a hole designed for the Pi camera.

For the software, [Jason] turned to Node JS, and LIRC, a piece of software that decodes IR signals. With the GPIO pin defined, [Jason] set up the driver and used the Sonos HTTP API to send commands to his audio unit. There’s a lot of futzing about with text files for this build, but the results speak for themselves: [Jason] can now use a universal remote with everything in his home stereo now.

Ultrasonic Raspberry Pi Piano

April 22, 2017 by 9 Comments

Cheap stuff gets our creative juices flowing. Case in point? [Andy Grove] built an eight-sensor HC-SR04 breakout board, because the ultrasonic distance sensors in question are so affordable that a hacker can hardly avoid ordering them by the dozen. He originally built it for robotics, but then it’s just a few lines of code to turn it into a gesture-controllable musical instrument. Check out the video, embedded below, for an overview of the features.

His Octasonic breakout board is just an AVR in disguise — it reads from eight ultrasonic sensors and delivers a single SPI result to whatever other controller is serving as the brains. In the “piano” demo, that’s a Raspberry Pi, so he needed the usual 5 V to 3.3 V level shifting in between.

The rest is code on the Pi that enables gestures to play notes, change musical instruments, and even shut the Pi down. The Pi code is written in Rust, and up on GitHub. An Instructable has more detail on the hookups.

All in all, building a “piano” out of robot parts is surely a case of having a hammer and every problem looking like a nail, but we find some of the resulting nail-sculptures arise that way. This isn’t the first time we’ve seen an eight-sensor ultrasonic setup before, either. Is 2017 going to be the year of ultrasonic sensor projects? Continue reading “Ultrasonic Raspberry Pi Piano” →

Discontinued Nintendo Consoles And Raspberry Pis

April 19, 2017 by 24 Comments

Nintendo has discontinued a Classic gaming console. It’s a pity, yes, but with the release of Nintendo’s new gaming console, they probably have bigger fish to fry. That doesn’t mean these discontinued Nintendo consoles will die a slow, miserable death locked away in a closet; at least one of them will live on with the heart of a Raspberry Pi.

This is a project [Liam] has been working on since 2012, just after he got the first edition of the Raspberry Pi. While some people were figuring out how to stuff the Pi inside a Nintendo Entertainment System or a Super Nintendo Entertainment System, [Liam] decided to embed the Pi inside a console of a more recent vintage: the Nintendo GameCube.

The first phase of this project was simply to get the Pi running inside the enclosure of the non-working GameCube he picked up. The power supply in this console was well designed, and after a quick perusal through some online documentation, [Liam] found a stable 5V with enough amps to power the Pi. After ripping out the internals of this console with the help of a quickly hacked together ‘Nintendo screwdriver’, [Liam] had a perfectly functional Pi enclosed in a Nintendo chassis.

Time marches on, and after a while, the Raspberry Pi 2 was released. By this time, retro emulation was hitting the big time, and [Liam] decided it was time for an upgrade. He disassembled this Nintendo console again, routed new wires and inputs to the original controller ports, and used a Dremel to route a few holes for the HDMI and SD card slot.

With the addition of a few SNES-inspired USB controllers, RetroPi, and a few ROMs, [Liam] has a wonderful console full of classic emulation goodness, packaged in an enclosure Nintendo isn’t making any more.

Networking: Pin The Tail On The Headless Raspberry Pi

April 18, 2017 by 69 Comments

Eager to get deeper into robotics after dipping my toe in the water with my BB-8 droid, I purchased a Raspberry Pi 3 Model B. The first step was to connect to it. But while it has built-in 802.11n wireless, I at first didn’t have a wireless access point, though I eventually did get one. That meant I went through different ways of finding it and connecting to it with my desktop computer. Surely there are others seeking to do the same so let’s take a look at the secret incantations used to connect a Pi to a computer directly, and indirectly.

Continue reading “Networking: Pin The Tail On The Headless Raspberry Pi” →

Brazil Wins The Raspberry Pi Overclocking Olympics

April 18, 2017 by 20 Comments

[Alex Rissato] proudly reports that he now holds the record for highest benchmark score on HWBOT (machine translation); something he sees not only as a personal achievement but admirably, of national pride. Overclocking a Raspberry Pi is not as simple as achieving the highest operational clock rate. A record constitutes just the right combination of CPU clock, memory clock, GPU clock and finally the CPU core voltage. If you’ve managed to produce that special sauce, the combination must be satisfactorily cooled and most importantly be stable enough to pass an actual performance benchmark.

More POWAAA to the CPU!

[Alex] realized that the main hurdle to achieving the desired CPU clock was the internally generated and hence restricted, CPU core voltage; This is externally LC filtered and routed back to the CPU on a stock Pi. [Alex] de-soldered the filter on the PCB and provided the CPU with an externally generated core voltage.

Next, the cooling had to be tended to. Air cooling simply wouldn’t cut it, so a Peltier based heatsink interface had to be devised with the hot side immersed in a bucket of salt water. All of this translated to a comfy 16C at a clock speed of 1600 MHz.

Was all the effort justified? We certainly think it was! Despite falling short of the Pi zero CPU clock rate record, currently set at 1620MHz,  [Alex] earned the top spot in the HWBOT Prime overclocking benchmark. Brazil can now certainly add this to its trophy cabinet, arguably overshadowing the 129 Olympic medals.

Detect Cars Running Stop Signs (and Squirrels Running Across The Roof)

April 12, 2017 by 40 Comments

In order to avoid the traffic and delays on a major thoroughfare, cars take the road behind [Devin Gaffney]’s house, but he noticed a lot of cars didn’t bother to stop at the stop sign. He had a Raspberry Pi and a camera, so he set them up to detect the violating cars.

His setup is pretty standard – Raspberry Pi and camera pointed outside at the intersection. He’s running OpenCV and using machine learning to detect the cars and determine if they have run the stop sign or not. His website has some nice charts showing when the violations occurred by hour and by day of the week. Also on the site are links that you can use to help train the system in noticing cars, cars that run the stop sign, determining if there’s enough of the video to determine if there’s a violation, and whether or not there’s a car going the wrong way through the intersection.

This is an interesting use of the Pi and OpenCV; there’s no guarantee that this will help the people of [Devin]’s neighborhood, but hopefully gives them some ammunition (assuming they want something done about the intersection.) It’s a cheap and easy setup and it’s nice to let the community have a hand in training the system.

For more OpenCV, check out this article on taking the perfect jump shot or this one which tries to quantify cloudiness.

Continue reading “Detect Cars Running Stop Signs (and Squirrels Running Across The Roof)” →