Pi

68 Articles

Improving Raspberry Pi Disk Performance

December 29, 2016 by 31 Comments

Usually, you think of solid state storage as faster than a rotating hard drive. However, in the case of the Raspberry Pi, the solid state “disk drive” is a memory card that uses a serial interface. So while a 7200 RPM SATA drive might get speeds in excess of 100MB/s, the Pi’s performance is significantly less.

[Rusher] uses the Gluster distributed file system and Docker on his Raspberry Pi. He measured write performance to be a sluggish 1MB/s (and the root file system was clocking in at just over 40MB/s).

There are an endless number of settings you could tweak, but [Rusher] heuristically picked a few he thought would have an impact. After some experimentation, he managed 5MB/s on Gluster and increased the normal file system to 46 MB/s.

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Orange Pi Releases Two Boards

November 7, 2016 by 134 Comments

A few years ago, someone figured out small, cheap ARM Linux boards are really, really useful, extremely popular, sell very well, blink LEDs, and are able to open the doors of engineering and computer science to everyone. There is one giant manufacturer of these cheap ARM Linux boards whose mere mention guarantees us a few thousand extra clicks on this article. There are other manufacturers of these boards, though, and there is no benevolent monopoly; the smaller manufacturers of these boards should bring new features and better specs to the ARM Linux board ecosystem. A drop of water in a tide that lifts all boats. Something like that.

This week, Orange Pi, not the largest manufacturer of these small ARM Linux boards, has released two new boards. The Orange Pi Zero is an inexpensive, quad-core ARM Cortex A7 Linux board with 256 MB or 512 MB of RAM. The Orange Pi PC 2 is the slightly pricier quad-core ARM Cortex-A53 board with 1 GB of RAM and a layout that can only be described as cattywampus. We all know where the inspiration for these boards came from. The price for these boards, less shipping, is $6.99 USD and $19.98 USD, respectively.

The Orange Pi Zero uses the Allwinner H2 SoC, and courageously does not use the standard 40-pin header of another very popular line of single board computers, although the 26-pin bank of pins is compatible with the first version of the board you’re thinking about. Also on board the Orange Pi Zero is WiFi provided by an XR819 chipset, Ethernet, a Mali400MP2 GPU, USB 2.0, a microSD card slot, and a pin header for headphones, mic, TV out, and two more USB ports.

The significantly more powerful Orange Pi PC 2 sports a quad-core ARM Cortex-A53 SoC coupled to 1 GB of RAM. USB OTG, a trio of USB 2.0 ports, Ethernet, camera interface, and HDMI round out the rest of the board.

Both of Orange Pi’s recent offerings are Allwinner boards. This family of SoCs have famously terrible support in Linux, and the last Allwinner Cortex-A53, that we couldn’t really review, was terrible. Although the Orange Pi Zero and Orange Pi PC 2 are new boards and surely software is still being written, history indicates the patches written for this SoC will not be sent upstream, and these boards will be frozen in time.

If you’re looking for a cheap Linux board with a WiFi chipset that might work, The Orange Pi Zero is very interesting. The Orange Pi PC 2 does have slightly impressive specs for the price. When you buy a single board, though, you’re buying into a community dedicated to improving Linux support on the board. From what I’ve seen, that support probably won’t be coming but I will be happy to be proven wrong.

Impressive Pi System Controls Large Office

October 22, 2016 by 35 Comments

A pile of Raspberry Pis isn’t what would spring to mind for most people when building a system to control a large office, but most people aren’t [Kamil Górski]. He decided to use Pis to run the office of his company Monterail when they moved to a larger space. The system they built is one of the largest Pi installations we have seen, controlling the lights, TVs, speakers and door access. It can all be controlled through a web interface, so anyone on the network can turn the lights on or off, check if a room is occupied or send sound and video to the fancy AV system in the conference room. He even hacked a bunch of HDMI switches so that every TV can show the same image if everyone wants to watch the same event. Even the radio station that plays in the lounge is controlled remotely from an employee slack channel.

The system is run on five Pis, one of which acts as a master, while the others are connected to each of the TVs, running Chrome in console mode being remotely controlled through the Chrome Debugging Protocol.  That allows anyone on the network to control the display and send content to it. One interesting thing to note: [Kamil] freely admits that this is a bespoke system that couldn’t be easily sold as a product. Nothing wrong with that, but he decided to build in some backups: if the whole system fails, all of the lights, doors, and other devices can still be controlled through old-school switches, keys, and remote controls. Even a full system crash doesn’t render the office unusable. That’s a wide precaution that many people forget in systems like this.

Counting Eggs With A Webcam

October 14, 2016 by 14 Comments

You’ll have to dig out your French dictionary (or Google translate) for this one, but it is worth it. [Nicolas Giraud] has been experimenting with ways to use a webcam to detect the number of eggs chickens have laid in a chicken coop. This page documents these experiments using a number of different algorithms to automatically detect the number of eggs and notify the owner. The system is simple, built around a Pi running Debian Jesse Lite and a cheap USB webcam. An LED running off one of the GPIO pins illuminates the eggs, and the camera then captures the image for analysis.

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Rainy Day Fun By Calculating Pi

August 24, 2016 by 14 Comments

If you need a truly random event generator, just wait till your next rainstorm. Whether any given spot on the ground is hit by a drop at a particular time is anyone’s guess, and such randomness is key to this simple rig that estimates the value of pi using raindrop sensors.

You may recall [AlphaPhoenix]’s recent electroshock Settlers of Catan expeditor. The idea with this less shocking build is to estimate the value of pi using the ratio of the area of a square sensor to a circular one. Simple piezo transducers serve as impact sensors that feed an Arduino and count the relative number of raindrops hitting the sensors. In the first video below, we see that as more data accumulates, the Arduino’s estimate of pi eventually converges on the well-known 3.14159 value. The second video has details of the math behind the method, plus a discussion of the real-world problems that cropped up during testing — turns out that waterproofing and grounding were both key to noise-free data from the sensor pads.

In the end, [AlphaPhoenix] isn’t proving anything new, but we like the method here and can see applications for it. What about using such sensors to detect individual popcorn kernels popping to demonstrate the Gaussian distribution? We also can’t help but think of other ways to measure raindrops; how about strain gauges that weigh the rainwater as it accumulates differentially in square and circular containers? Share your ideas in the comments below.

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Another Small Linux Computer With Pi In Its Name

July 13, 2016 by 78 Comments

Since the introduction of the Raspberry Pi, the embedded Linux scene has been rocked by well supported hardware that is produced in quantity, a company that won’t go out of business in six months, and a huge user base. Yes, there are a few small problems with the Raspberry Pi and its foundation – some stuff is still closed source, the Foundation itself plays things close to their chests, and there are some weird binary blobs somebody will eventually reverse engineer. Viewed against the competition, though, nothing else compares.

Here’s the NanoPi Neo, the latest quad-core Allwinner board from a company in China you’ve never heard of.

The NanoPi Neo is someone’s answer to the Raspberry Pi Zero, the very small and very cheap single board Linux computer whose out-of-stock percentage has led some to claim it’s completely fake and a media conspiracy. The NanoPi Zero features an Allwinner H3 quad-core Cortex-A7 running at 1.2 GHz, 256MB RAM, with a 512MB version being released shortly. Unlike the Raspberry Pi Zero, the NanoPi Neo features a 10/100 Ethernet port. No, it does not have PoE.

As with anything comparing itself to the Raspberry Pi Zero, only two things are important: size and price. The NanoPi Neo is a mere 40mm square, compared to the 65x30mm measurements of the Pi Zero. The NanoPi Neo is available for $7.99, with $5 shipping to the US. Yes, for just three dollars more than a Pi Zero with shipping, you get a poorly supported Linux board. What a time to be alive.

If you’re looking for another wonderful tale of what happens with cheap, powerful ARM chips and contract manufacturers in China, check out my review of the Pine64.

Hackaday Prize Entry: A Raspberry Pi Project

June 23, 2016 by 40 Comments

There’s no piece of technology that has been more useful, more influential on the next generation of sysadmins and engineers, and more polarizing than the Raspberry Pi. For $35 (or just $5), you get a complete single board computer, capable of running Linux, and powerful enough to do useful work. For the 2016 Hackaday Prize, [Arsenijs] has created the perfect Raspberry Pi project. It’s everything you expect a Pi-powered project to be, and more.

While the Raspberry Pi, and the community surrounding the Raspberry Pi, get a lot of flak for the relatively simple approach to most projects which are effectively just casemods, critics of these projects forget the historical context of tiny personal computers. Back in the early ‘aughts, when Mini ITX motherboards were just being released, websites popped up that would feature Mini ITX casemods and nothing else. While computers stuffed into an NES, an old radio, or the AMD logo are rather banal projects today, I assure you they were just as pedestrian 15 years ago as well. Still, the creators of these Mini ITX case mods became the hardware hackers of today. It all started with simple builds, a Dremel, and some Bondo.

[Arsenijs] takes his Raspberry Pi project a bit further than a simple casemod, drawing influence from a Raspberry Pi smartphone, a Raspberry Pi security system, a Portable Raspberry Pi, and a Raspberry Pi wrist computer. These are all excellent projects in their own right, but [Arsenijs] is putting his own special twist on the project: he’s using a Raspberry Pi, and a few Raspberry Pi accessories.

While this project is first and foremost a Raspberry Pi project, [Arsenijs] isn’t limiting himself to the platform with the Broadcom chip. The team behind this Raspberry Pi project was busy porting the project to Odroid when the Banana Pi came out. This changed everything, a refactor was required, and then the Orange Pi was announced. Keeping up with technology is hard, and is a big factor in why this Raspberry Pi project hasn’t delivered yet. You can say a lot of things about the Raspberry Pi foundation, but at least their boards make a good attempt at forward compatibility.

Already [Arsenijs]’ Raspberry Pi project is one of the more popular projects on Hackaday.io, and is in the running for being one of the most popular projects in this year’s Hackaday Prize. Whether that popularity will translate into a minor win for this year’s Hackaday Prize remains to be seen, but it seems for [Arsenijs] that doesn’t matter; he’s already on the bleeding edge of Raspberry Pi projects.

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