rasberry pi

6 Articles

A Lightweight Smart Home Server

June 6, 2023 by 29 Comments

Working towards automating a few things in a home often seems simple on the surface, but it’s easy for these projects to snowball into dozens of sensors and various servos, switches, and cameras strewn about one’s living space. The same sort of feature creep sneaks into some of the more popular self-hosted home server platforms as well, with things like openHAB requiring so much computing power that they barely function on something like a Raspberry Pi. [Paulo] thought there should be a more lightweight way of tackling a project like this, and set about building his own smart home server with help from some interesting software.

The project is based around the Dirigera hub from Ikea, partially because [Paulo] is planning to use other smart home devices from Ikea as he can easily find them where he is, and also because these devices tend to use Zigbee, a non-proprietary communications standard. This means that if he ever wants to swap out the hub for another one in the future, it won’t be difficult to do. From here the major hurdle is that using the default software from these devices is fairly limiting, so [Paulo] reached for a Raspbee 2 Zigbee gateway for use with a Raspberry Pi and an extremely lightweight and customizable web server called Mako to make this happen. Using Lua as the high-level language to tie everything together he was able to easily deploy the server to control the Ikea hub and devices and automate them in any way he sees fit.

While it is true that software like openHAB and others already exists to do virtually any home automation task that could be imagined, if you’re looking to do something with a bare minimum of computing power something like [Paulo]’s solution is likely going to be the fastest and most reliable method of getting a few things automated around the home. If you’re looking for something completely open source and built from the ground up, though, we have seen a few alternative smart home solutions like this one which don’t rely on any proprietary hardware or software, but do take a little bit more effort on the user’s part.

A Dedicated GPU For Your Favorite SBC

May 5, 2023 by 35 Comments

The Raspberry Pi is famous for its low cost, versatile and open Linux environment, and plentiful I/O, making it a perfect device not only for its originally-intended educational purposes but for basically every hobbyist from gardeners to roboticists to amateur radio operators. Most builds tend to make use of the GPIO pins which allow easy connections to various peripherals and sensors, but the Pi also supports PCI devices which means that, in theory, it could use a GPU in much the same way that a modern computer would. After plenty of testing and development, [Jeff Geerling] brings us this custom graphics card interface for the Raspberry Pi.

The testing for all of these graphics cards has been done with a Pi Compute Module 4 and the end result is an interface device which looks much like a graphics card itself. It splits the PCI bus out onto a more familiar x16 slot connector and adds physical connections for power, USB, and Ethernet. When plugged into the carrier board, the Compute Module can be attached to any of a number of graphics cards, including the latest and highest-end of Nvidia and AMD offerings.

Perhaps unsurprisingly, though, the 4090 and 7900 cards don’t work with the Raspberry Pi. This is partially due to the 32-bit limitations of the Pi and other memory mapping issues, but even after attempting some workarounds Nvidia’s cards aren’t open-source enough to test properly (although the card is recognized by the Pi) and AMD’s drivers crash the system even after compiling a custom kernel. [Jeff] did find an Nvidia card that worked, although it requires using the USB interface and second-hand cards are selling for around $3000 USD. For a more economical choice there are some other graphics cards that he was eventually able to get working, albeit not with perfect performance, including some of the ones we’ve seen him test already.

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You Don’t Need That Bulky CRT Oscilloscope Anymore

June 5, 2019 by 92 Comments

While it might be nice to use a $4,000 oscilloscope in a lab at a university or well-funded corporate environment, a good portion of us won’t have access to that kind of equipment in our own home shops. There are a few ways of getting a working oscilloscope without breaking the bank, though. One option is to find old CRT-based unit for maybe $50 on craigslist which might still have 60% of its original 1970s-era equipment still operational. A more reliable, and similarly-priced, way of getting an oscilloscope is to just convert a device you already have.

The EspoTek Labrador is an open-source way of converting a Raspberry Pi, Android device, or even a regular run-of-the-mill computer into a working oscilloscope. It’s a small USB device with about a two square inch PCB footprint that includes some other features as well like a signal generator and logic analyzer. It’s based on an ATxmega which is your standard Arduino-style AVR microcontroller but geared for low power usage. It looks as though it is pretty simple to use as well, and the only requirements are that you can install the software needed for the device on whatever computing platform you decide to use.

While the Labrador is available for sale at their website, it is definitely a bonus when companies offer products like this but also release the hardware and software as open source. That’s certainly a good way to get our attention, at least. You can build your own if you’d like, but if you’d rather save the time you have pre-built options. And it doesn’t hurt that most of the reviews of this product seem to be very favorable (although we haven’t tried one out ourselves). If you’d prefer an option without a company backing it, though, we have you covered there too.

FatPiBoy: Respin Game Boy With A Pop-Out Controller

November 20, 2017 by 5 Comments

Have you ever found yourself wishing you had a clone of the Game Boy, except it was actually twice as wide, and instead of holding it in your hands you pop a tiny separate controller out of the middle and play it that way? No? Well, neither have we. But that didn’t stop [Christian Reinbacher] from designing and building exactly that, and by the looks of the finished product, we have to say he might be onto something.

To be fair, the charmingly-named FatPiBoy is not really meant to be played like the GameBoy of yesteryear. It’s more like a game console with built in display; you prop the console up on something, and then remove the controller from the system and play that way.

The controller itself is a commercial product, the 8bitdo Zero, but [Christian] based the rest of the system on parts intended for the Adafruit PiGRRL. For the battery, [Christian] used a 4,500 mAh pack that was originally from his Nexus 7 tablet; a tip to keep in mind next time you’re looking for a big and cheap lithium-ion battery.

[Christian] notes that the case design isn’t perfect. There’s currently no external access to the Pi’s USB ports, and the recess for the 8bitdo Zero could be a few millimeters deeper. Still, we think he did an excellent job finishing the case and giving it a professional look; the case and controller look like nearly a perfect match.

This isn’t the first time we’ve seen a Raspberry Pi put on a GameBoy costume, but the FatPiBoy does bring something new to the table with its removable controller. Of course, if you think the controller [Christian] selected for this build is a bit too small, you can always substitute your own…

SegaPi Zero Shows Game Gear Some Respect

October 21, 2017 by 15 Comments

If you were a gamer in 1991, you were presented with what seemed like an easy enough choice: you could get a Nintendo Game Boy, the gray brick with a slightly nauseating green-tinted screen that was already a couple of years old, or you could get yourself a glorious new Sega Game Gear. With full color display and games that were ported straight from Sega’s home consoles, it seemed like the Game Gear was the true future of portable gaming. But of course, that’s not how things actually went. In reality, technical issues like abysmal battery life held the Game Gear back, and conversely Nintendo and their partners were able to squeeze so much entertainment out of the Game Boy that they didn’t even bother creating a true successor for it until nearly a decade after its release.

While the Game Gear was a commercial failure compared to the Game Boy back in the 1990s and never got an official successor, it’s interesting to think of what may have been. A hypothetical follow-up to the Game Gear was the inspiration for the SegaPi Zeo created by [Halakor]. Featuring rechargeable batteries, more face buttons, and a “console” mode where you can connect it to a TV, it plays to the original Game Gear’s strengths and improves on its weaknesses.

As the name implies the SegaPi Zero is powered by the Raspberry Pi Zero, and an Arduino Pro Micro handles user input by tactile switches mounted behind all the face buttons. A TP4056 charging module and step-up converter are also hiding in there, which take care of the six 3.7 lithium-Ion 14500 batteries nestled into the original battery compartments. With a total capacity of roughly 4,500 mAh, the SegaPi Zero should be able to improve upon the 3 – 4 hour battery life that helped doom the original version.

There’s no shortage of projects that cram a Raspberry Pi into a classic game system, but more often than not, they tend to be Nintendo machines. It could simply be out of nostalgia for Nintendo’s past glories, but personally we’re happy to see another entry into the fairly short list of Sega hacks.

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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