raspberry pi

1651 Articles

Tracking Boats And Ships In Real Time At The Same Time

October 22, 2020 by 15 Comments

Software-defined radio came on the hacker scene in a big way less than a decade ago thanks to the discovery that a small USB-based TV tuner dongle could be used for receiving all kinds of radio transmissions. Two popular projects from that era are tracking nearby airplanes and boats in real time. Of course, these projects rely on different frequencies and protocols, but if you live in a major port city like [Ian] then his project that combines both into a single user interface might be of interest.

This project uses an RTL-SDR dongle for the marine traffic portion of the project, but steps up to a FlightAware Pro dongle for receiving telemetry from airplanes. Two separate antennas are needed for this, and all of the information is gathered and handled by a pair of Raspberry Pis. The Pis communicate with various marine and air traffic databases as well as handles the custom user interface that knits both sets of information together. This interface was custom-built from a previous project of his and was repurposed slightly to fit the needs of this one.

This is a great project that goes into a lot of interesting detail about how the web traffic moves and how the UI works, so even if you’re not into software-defined radio it might be worth a look. However, it’s also worth noting that it hasn’t been easier to set up a system like this thanks to the abundance and low price of RTL-SDR dongles and the software tools that make setting them up a breeze.

Raspberry Pi And Raspberry Pi Spy: This Is How Trademark SNAFUs Should Be Handled

October 20, 2020 by 29 Comments

In the eight years or so since the Raspberry Pi first landed as tangible hardware, we’ve all dealt with the Pi folks whether as customers or through their many online support and outreach activities. They’ve provided our community with the seed that led to an explosion of inexpensive Linux-capable single board computers, while their own offerings have powered so many of the projects we have featured here. Their heart lies in their educational remit, but they have also become an indispensable part of our community.

The statement from the Pi Foundation’s Philip Colligan.

Thus it was a surprise when [Raspberry Pi Spy], a long-time commentator on all things Pi, received a legal notice from the Raspberry Pi Foundation that their use of the Raspberry Pi name contravened the acceptable use guidelines and demanding that all content be removed and the domains be handed over. Some consternation ensued, before Pi foundation boss [Philip Colligan] released a statement retracting the original letter and explaining that the incident was the result of an over-zealous legal adviser and that the Foundation has no wish to undermine the Pi community.

All’s well that ends well, but what just happened? In the first instance, it’s natural for any organisation to wish to protect their brand, and there would be plenty of unscrupulous entities ready to sell fake Pi products were the Foundation not active in asserting their rights. In this case it seems that it was the use of the full Raspberry Pi trademark in a domain name that triggered the letter and not the fair-use blogging about the Pi products. We can see that however much we might wish otherwise it was not without legal merit. There have been numerous cybersquatting cases heard since the creation of the Web, and even though some of them have been on more dubious ground than others it remains a well-trodden path.

Where this story differs from so many others though is that the Pi Foundation acted with common sense in withdrawing the notice issued against a member of its community. It is inevitable that sometimes even the best of us can take regrettable paths by whatever means, and respect is earned by how such situations are resolved. We applaud the Pi folks for their swift action in this matter, we’d suggest to anyone that they take care when registering domain names, and we suspect that somewhere a legal adviser will be in the doghouse. But that all such incidents in our community could be resolved with such ease.

Thinking About Creating A Raspberry Pi Replacement?

October 20, 2020 by 66 Comments

If you’ve ever wanted to try your hand at creating a Raspberry Pi-like board for yourself, you should check out [Jay Carlson’s] review of 10 different Linux-capable SoCs. Back in the 1960s, a computer was multiple refrigerator-sized boxes with thousands of interconnections and building one from scratch was only a dream for most people. Then ICs came and put all the most important parts in a little relatively inexpensive IC package and homebrew computing became much more accessible. Systems on Chip (SoC) has carried that even further, making it easier than ever to create entire systems, like the Pi and its many competitors.

Only a few years ago, making an SoC was still a big project because the vendors often didn’t want to release documentation to the public. In addition, most of the parts use ball grid array (BGA) packaging. BGA parts can be hard to work with, and require a multilayer PC board. Sure, you can’t plug these into a typical solderless breadboard. But working with these relatively large BGAs isn’t that hard and multilayer boards are now comparatively cheap. [Jay] reports that he got cheap PCBs and used a hot plate to build each board, and has some sage advice on how to do it.

Continue reading “Thinking About Creating A Raspberry Pi Replacement?” →

New Raspberry Pi 4 Compute Module: So Long SO-DIMM, Hello PCIe!

October 19, 2020 by 151 Comments

The brand new Raspberry Pi Compute Module 4 (CM4) was just released! Surprised? Nope, and we’re not either — the Raspberry Pi Foundation had hinted that it was going to release a compute module for the 4-series for a long while.

The form factor got a total overhaul, but there’s bigger changes in this little beastie than are visible at first glance, and we’re going to walk you through most of them. The foremost bonuses are the easy implementation of PCIe and NVMe, making it possible to get data in and out of SSDs ridiculously fast. Combined with optional WiFi/Bluetooth and easily designed Gigabit Ethernet, the CM4 is a connectivity monster.

One of the classic want-to-build-it-with-a-Pi projects is the ultra-fast home NAS. The CM4 makes this finally possible.

If you don’t know the compute modules, they are stripped-down versions of what you probably think of as a Raspberry Pi, which is officially known as the “Model B” form-factor. Aimed at commercial applications, the compute modules lack many of the creature comforts of their bigger siblings, but they trade those for flexibility in design and allow for some extra functionality.

The compute modules aren’t exactly beginner friendly, but we’re positively impressed by how far Team Raspberry has been able to make this module accessible to the intermediate hacker. Most of this is down to the open design of the IO Breakout board that also got released today. With completely open KiCAD design files, if you can edit and order a PCB, and then reflow-solder what arrives in the mail, you can design for the CM4. The benefit is a lighter, cheaper, and yet significantly more customizable platform that packs the power of the Raspberry Pi 4 into a low-profile 40 mm x 55 mm package.

So let’s see what’s new, and then look a little bit into what is necessary to incorporate a compute module into your own design.

Continue reading “New Raspberry Pi 4 Compute Module: So Long SO-DIMM, Hello PCIe!” →

Robot Travels The World

October 17, 2020 by 7 Comments

Around the World in 80 Days may have been an impressive feat of international travel in a world before widespread air transit. In modern times though, it’s not even necessary to leave your home in order to travel around the world. To that end, [Norbert] is attempting to accomplish this journey using a robot that will do the traveling for him as part of this year’s Virtual Maker Faire.

The robot is called the World Tour Robot, and the idea for it is to be small enough to ship to each new location around the world and be simple enough to be repaired easily. It is driven by two servo motors and controlled by a Raspberry Pi which also handles a small camera. Once at its location, it can connect to the internet and then be able to be controlled through a web interface. Locations are selected by application, and the robot is either handed off to the next person in the chain or put back in a box to be shipped.

The robot hasn’t left for its maiden voyage just yet but [Norbert] plans to get it started soon. Hopefully there are enough interesting places for this robot to explore on its trip around the world, although it’s probably best to avoid Philadelphia as it is known to be unfriendly to robots.

Cheap All-Sky Camera Is Easy As Pi

October 14, 2020 by 28 Comments

Combining a Raspberry Pi HQ camera and a waterproof housing, [jippo12] made an all-sky, all-Pi meteorite tracking camera on the cheap, and it takes fantastic photos of the heavens. It’s even got its own YouTube channel. Inside there’s a Raspberry Pi 4 plus an HQ camera to take the pictures. But there’s also a system in place to keep everything warm and working properly. It uses a Raspberry Pi 3+, a temperature sensor, and a relay control HAT to pump pixies through a couple of 10 W resistors, making just enough heat to warm up the dome to keep it from fogging.

A few years ago, we reported that NASA was tracking meteorites (or fireballs, if you prefer) with a distributed network of all-sky cameras — cameras with 360° views of the night sky. Soon after, we found out that the French were doing something quite similar with their FRIPON network. We pondered how cool it would be to have a hacker network of these things, but zut alors! Have you seen the prices of these things?  Nice hack, [jippo12]!

Rather do things the old fashioned way? Dust off that DSLR, fire up that printer, and check out OpenAstroTracker.

Running Way More LED Strips On A Raspberry Pi With DMA

October 12, 2020 by 18 Comments

The Raspberry Pi is a powerful computer in a compact form factor, making it highly useful for all manner of projects. However, it lacks some of the IO capabilities you might find on a common microcontroller. This is most apparent when it comes to running addressable LED strings. Normally, this is done using the Pi’s PWM or audio output, and is limited to just a couple of short strings. However, [Jeremy P Bentham] has found a way to leverage the Pi’s hardware to overcome these limitations.

The trick is using the Raspberry Pi’s little-documented Secondary Memory Interface. The SMI hardware allows the Pi to shift out data to 8 or 16 I/O pins in parallel using direct memory access (DMA), with fast and accurate timing. This makes it perfect for generating signals such as those used by WS2812B LEDs, also known as NeoPixels.

With [Jeremy]’s code and the right supporting hardware, it’s possible to run up to 16 LED strips of arbitrary length from the Raspberry Pi. [Jeremy] does a great job outlining how it all works, covering everything from the data format used by WS2812B LEDs to the way cache needs to be handled to avoid garbled data. The hack works on all Pis, from the humble Pi Zero to the powerful Pi 4. Thanks to using DMA, the technique doesn’t overload the CPU, so performance should be good across the board.

Of course, there are other ways to drive a ton of LEDs; we’ve seen 20,000 running on an ESP32, for example.

[Thanks to Petiepooo for the tip!]