Raspberry Pi

1848 Articles

A Tiny Train Departure Board, Just Like The Real Thing

August 5, 2019 by 8 Comments

If you travel on the British rail system, you’ll be familiar with the ubiquitous orange dot-matrix departure display boards. At a glance they tell you the expected arrival times of the next few trains, where they are headed, and at the bottom the current time.  [Chris Crocker-White] was inspired by a Tweet to recreate one of these displays in miniature and hang it under his monitor.

The hardware is a Raspberry Pi Zero with an OLED screen, in a custom 3D-printed case. A soldered USB cable takes power from the monitor’s USB ports. Software wise it’s a demonstration vehicle for the Balena cloud service that pulls its data from their transport API, but the choice of dot matrix typeface is perfect and absolutely looks the part.

There is some question as to whether a project such as this one should need a cloud service as its backend, and of course it serves as a demonstration piece rather than a definitive way to enact a departure board. It does however bring a ready-packaged API for transport data, which given that many data sources can be opaque, is a useful feature.

Train time displays seem to be a popular choice on the Eastern side of the Atlantic, here’s another British one, and one from Ireland.

Thanks [Pyrofer] for the tip.

High Performance Stereo Computer Vision For The Raspberry Pi

August 3, 2019 by 30 Comments

Up until now, running any kind of computer vision system on the Raspberry Pi has been rather underwhelming, even with the addition of products such as the Movidius Neural Compute Stick. Looking to improve on the performance situation while still enjoying the benefits of the Raspberry Pi community, [Brandon] and his team have been working on Luxonis DepthAI. The project uses a carrier board to mate a Myriad X VPU and a suite of cameras to the Raspberry Pi Compute Module, and the performance gains so far have been very promising.

So how does it work? Twin grayscale cameras allow the system to perceive depth, or distance, which is used to produce a “heat map”; ideal for tasks such as obstacle avoidance. At the same time, the high-resolution color camera can be used for object detection and tracking. According to [Brandon], bypassing the Pi’s CPU and sending all processed data via USB gives a roughly 5x performance boost, enabling the full potential of the main Intel Myriad X chip to be unleashed.

For detecting standard objects like people or faces, it will be fairly easy to get up and running with software such as OpenVino, which is already quite mature on the Raspberry Pi. We’re curious about how the system will handle custom models, but no doubt [Brandon’s] team will help improve this situation for the future.

The project is very much in an active state of development, which is exactly what we’d expect for an entry into the 2019 Hackaday Prize. Right now the cameras aren’t necessarily ideal, for example the depth sensors are a bit too close together to be very effective, but the team is still fine tuning their hardware selection. Ultimately the goal is to make a device that helps bikers avoid dangerous collisions, and we’ve very interested to watch the project evolve.

The video after the break shows the stereoscopic heat map in action. The hand is displayed as a warm yellow as it’s relatively close compared to the blue background. We’ve covered the combination Raspberry Pi and the Movidius USB stick in the past, but the stereo vision performance improvements Luxonis DepthAI really takes it to another level.

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Jazzberry Bakes The Pi Into A Mechanical Keyboard

July 26, 2019 by 17 Comments

If you hang around Hackaday long enough, pretty soon you’ll start to see some patterns emerging. As the nexus of all things awesome in the hacking world, our front page offers a unique vantage point by which you can see what’s getting folks excited this particular month, year, or decade. Right now we can tell you hackers love the Raspberry Pi, 3D printing, and perhaps above all, they can’t get enough mechanical keyboards.

So that makes the Jazzberry by [Mattis Folkestad] something of a perfect storm in the hacker world. The project uses a 3D printed enclosure to combine a Raspberry Pi 3B+ and an Ajazz AK33 mechanical keyboard into a single unit like the home computers of old. Honestly, we’re just glad he didn’t sneak an ESP8266 in there; as the resulting combination might have been enough to crash the site.

That being said, we can’t help but notice there’s a lot of open space inside the 3D printed enclosure. Right now there’s nothing inside but the Raspberry Pi, which only takes up a fraction of the internal volume. Adding a battery and hard drive would be the logical next steps, but it could also be outfitted with a suite of radios and various other hacking and security research accoutrements. We’ve seen an influx of such builds over the last few months, and the Jazzberry seems like it could make a very slick entry into this burgeoning category of mobile pentesting devices.

The STL files are designed specifically for the combination of hardware that [Mattis] used, but it shouldn’t be too difficult to modify them for your own purposes. Even if you stick with the same AK33 keyboard, an upgrade to the impressively powerful Raspberry Pi 4 would be more than worth the time fiddling with the STLs in your CAD tool of choice. If you really want to go all in, add a display and you’re well on the way to that cyberdeck you’ve always wanted.

Exploring The Raspberry Pi 4 USB-C Issue In-Depth

July 16, 2019 by 117 Comments

It would be fair to say that the Raspberry Pi team hasn’t been without its share of hardware issues, with the Raspberry Pi 2 being camera shy, the Raspberry Pi PoE HAT suffering from a rather embarrassing USB power issue, and now the all-new Raspberry Pi 4 is the first to have USB-C power delivery, but it doesn’t do USB-C very well unless you go for a ‘dumb’ cable.

Join me below for a brief recap of those previous issues, and an in-depth summary of USB-C, the differences between regular and electronically marked (e-marked) cables, and why detection logic might be making your brand-new Raspberry Pi 4 look like an analogue set of headphones to the power delivery hardware.

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Raspberry Pi Cyberdeck Inspired By Rare MSX

July 16, 2019 by 11 Comments

When we see these cyberdeck builds, the goal is usually to just make something retro-futuristic enough to do William Gibson proud. There’s really no set formula, but offset screens coupled with large keyboards and a vague adherence to 1980s design language seem to be the most important tenets.

Granted the recent build by [lewisb42] still leans heavily on those common tropes, but at least there’s a clear lineage: his Raspberry Pi retro all-in-one is styled after a particularly rare bright red variant of the MSX that Sony released in Japan. Known as the HIT-BIT HB-101, some aficionados consider the circa-1984 machine to be the peak of MSX styling. Since getting his hands on a real one to retrofit wasn’t really an option, he had no choice but to attempt recreating some of the computer’s unique design elements from scratch.

The faceted sides were 3D printed in pieces, glued together, and then attached to a 1/4″ thick backplate made out of polycarbonate. For the “nose” piece under the keyboard, [lewisb42] actually used a piece of wood cut at the appropriate angles with a table saw. The top surface of the computer, which he calls the FLIPT-BIT, is actually made of individual pieces of foamed PVC sheet.

If all this sounds like a big jigsaw puzzle, that’s because it basically is. To smooth out the incongruous surfaces, he used a combination of wood putty, body filler, spot putty, and more time sanding then we’d care to think about. For the 3D printed surface details such as the screen bezel and faux cartridge slots, he used a coat of Smooth-On’s XTC-3D and yet more sanding. While [lewisb42] says the overall finish isn’t quite as good as he hoped, we think the overall look is fantastic considering the combination of construction techniques hiding under that glossy red paint job.

As for the electronics, there’s really no surprises there. The FLIPT-BIT uses a keyboard and touchpad from Perixx, a seven inch TFT display, and of course the Raspberry Pi 3. The display runs at 12 V so [lewisb42] used a combination of a generic laptop-style power supply and a 5 V step-down converter to keep everyone happy. While it doesn’t currently have a battery, it seems like there’s more than enough room inside the case to add one if he ever wants to go mobile.

If this build doesn’t properly scratch your Neuromancer itch, never fear. Just take a look at this decidedly less friendly-looking build that even includes a VR headset for properly jacking yourself into the matrix.

Make A Compatible Raspberry Pi Clone – But Your Pi Must Die

July 11, 2019 by 34 Comments

The world is awash with Raspberry Pi clones that boast fruity names, but those looking for a piece of the real thing will find their compatibility only goes so far. Shaky Linux distros abound and, with a few honourable exceptions, they are not for the faint-hearted. The reason that a market hasn’t emerged for fully-compatible clones is that the Pi people seem to have a monopoly on the world’s supply of the particular Broadcom SoCs that they use, forcing would-be competitors to source the brains of their outfit elsewhere.

It’s easy to buy a Raspberry Pi SoC though, if you don’t mind receiving a Raspberry Pi along with it. So to make a compatible Pi clone for space-constrained applications, the folks at Arducam removed the SoC from a Pi 3 and designed a surface-mount module board for it, making a 40 mm x 25 mm postage-stamp style system-on-module. It’s not a Raspberry Pi, but it runs Raspbian.

Their board is not one that they will be selling, but it does open up interesting possibilities for others with an eye to creating Pi boards in different form factors. It would be fascinating for example were somebody to produce an open-source module board for a Pi SoC. Some of you might be asking why the existing Compute Module was not suitable for them; in the write-up they cite mechanical issues with the SODIMM socket.

This isn’t the first compatible Pi clone we’ve seen. Aside from the intriguing but short-lived Odroid W there was another even smaller Arducam offering that never made it to market.

Giving The Pi 4 PCI Express

July 10, 2019 by 71 Comments

The release of the Raspberry Pi 4 brought us a new SoC, up to 4 Gigs of memory, and most importantly, got away from that janky USB to USB and Ethernet solution. The Raspberry Pi 4 has a PCI Express interface buried under some chips, and if you’re very good at soldering you can add a PCIe x1 device to the new best single board computer.

[Thomasz] took a look at the Raspberry Pi 4 and realized the new USB 3.0 chip is attached to the PCI Express interface on the SoC. That is, if you remove this chip and you have some very fine wires, you can patch in a real PCI Express slot. Removing the chip is easy enough with a hot air gun, although a few caps did get messed up. Throw that in an ultrasonic cleaner, and you have a blank canvas to work PCI magic.

This hack requires six wires, or three differential pairs, there’s a reference clock, a lane 0 transmit, and a lane zero receive. Working backwards from a PCI Express riser, [Thomasz] traced out these connections and soldered a few wires in. On the Pi side, a few capacitors were required to be compliant with the PCI Express spec, but the soldering isn’t too bad. You can do a lot with a small tip on an iron and a microscope.

The Pi was successfully wired up to a PCI Express riser card, along with the lines for ground, 5V, link reactivation, and a power good signal. The only thing left to do was to plug in a PCI card and test. This didn’t go as well as expected, because the PCI Express adapter didn’t like being enumerated by the Raspberry Pi kernel. In subsequent experiments, an Adaptec SAS controller worked. Does this mean external graphics cards for the Pi? No, not quite; this is only one lane of PCIe, where modern graphics cards require an x16 slot for the best performance. Still, if you’ve ever wanted a SCSI card for a Pi, this is the best option yet.