Pi Zero Digital Frame Kiosk Uses OTG Right

June 3, 2016 by Gerrit Coetzee 14 Comments

USB On-The-Go (OTG) is one of the fun aspects of the USB standard. There are feelings about the other aspects, but that one is alright. Regardless, [Francesco] realized one day that the £3 digital picture frames he purchased at a charity sale really didn’t care if the files on the thumb drive mysteriously changed all the time. It would just keep pulling and displaying the latest file at a blistering 0.2 frames per second. That’s right, the concept [Francesco] went after is to show changing data, even animations, with an update of one frame every five seconds!

His initial tests showed good for the concept — the Pi can easily emulate a mass storage device, feeding in data whenever the picture frame looks for it. In addition to the Pi Zero board he added an Ethernet shield, a voltage regulator, a camera, and even some infrared LEDS. We suppose there are dreams for the future.

He has been developing scripts for this rig by logging in through a VNC. A cron job runs his scripts at regular intervals, grabbing useful data and making it available as an image. For example, one script opens up the weather in Epiphany (a web browser), takes a screenshot, and saves that screenshot to the mass storage being emulated using USB OTG. The digital picture frame blissfully updates, unaware of its strange appendages. Now the real limiting factor is how much you can accomplish with your mad Bash skills.

A Quadcopter Controlled By A Pi Zero

February 16, 2016 by Brian Benchoff 57 Comments

Flight controllers for quadcopters and other drones are incredible pieces of engineering. Not only do these boards keep an aircraft level, they do so while keeping the drone in one place, or reading a GPS sensor and flying it from waypoint to waypoint. The latest of these flight controllers is built on everyone’s favorite $5 computer, the Raspberry Pi Zero.

The PXFmini controller and autopilot shield is the latest project from Erle Robotics that puts eight servo outputs on the Pi, barometer and IMU sensors, a power supply, and all the adapters to turn the Raspberry Pi Zero into a capable flight controller. Since the Pi Zero will have some computational horsepower left over after keeping a quadcopter level, there’s a possibility of some very cool peripherals. Erle Robotics has been working with depth cameras and Lidar on more than a few drones. This makes for some interesting applications we can only imagine now.

The schematics for the PXFmini are open source in the best traditions of the RC and drone community and will be available soon. You can check out a video of the FXPmini flying around an office below.

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Raspberry Pi Zero – Programming Over USB

Raspberry Pi Zero – Turning The Pi Into A USB Gadget, Over USB

January 7, 2016 by Gerrit Coetzee 18 Comments

[gbaman] has figured out a simpler way to program the new Raspberry Pi Zero over USB without modifying the board. Why is this useful? One example which appealed to us was setting the Zero’s USB port up as a mass storage device. Imagine plugging in your Pi powered robot, dragging and dropping a Python script into the mass storage device that shows up, and pressing a button on the robot to run the new script. Pretty fancy for $5.00.

You can get the PI to emulate a whole range of devices from a USB MIDI controller to a simple USB serial interface. We’re excited to see what uses people come up with. Unfortunately the Pi Zero is still out of stock most everywhere as we wait for the next production run to finish. Though if you’ve got one, why not check out a few of our thoughts and experiences with the device!

[gbaman] based his work off the work done by [Dave-0] and others over at the Raspberry Pi forums. [LadyAda] also has a version of this hack, which we covered, that involves soldering a header to the pi and using a UART adapter.

[via Hacker News]

Turning The Pi Zero Into A USB Gadget

December 27, 2015 by Brian Benchoff 60 Comments

The Raspberry Pi Zero is limited, or so everyone says, and everyone is trying to cram a USB hub and WiFi adapter on this tiny, tiny board. One thing a lot of people haven’t realized is that the Raspberry Pi Zero comes with a USB OTG port, meaning it can function as a USB device rather than a USB host. This means the Raspi can become a serial device with just a USB cable, an Ethernet device, MIDI device, camera, or just about anything else you can plug into a USB port. Adafruit has your back with a tutorial for using the USB OTG port as a serial and Ethernet interface, and the possible applications are extremely interesting.

The only requirement for using the USB OTG port for device applications is an update to the kernel. This is easily installed by dumping a few files on an SD card and a employing bit of command line wizardry. The simplest example is setting up the Pi Zero as a USB serial device, allowing anyone to log into a serial console on the Pi with just a USB cable.

A slightly more interesting application is setting up the Pi as an Ethernet gadget. This effectively tunnels all the networking on the Pi Zero through a USB cable and a separate computer. The instructions are extremely OS-specific, but the end result is the same: you can apt-get on a Pi Zero to your heart’s desire with a new kernel loaded onto the SD card and a USB cable.

This experimentation is just scratching the surface of what is possible with the OTG port on the Pi Zero. MIDI devices are easy, and with a ton of GPIOs, the Pi Zero itself could become a very interesting musical instrument. Want the Pi Zero to be a storage device? That’s easy too. The USB Gadget will end up being one of the most exciting uses for the Pi Zero, and we can’t wait to see what everyone will come up with next.

3 Nerds + 2 Days = Little Big Pixel

December 3, 2015 by Dan Maloney 2 Comments

Two days at a company sponsored hackathon? Sounds like fun to us! And productive too – the end result for [GuuzG] and two of his workmates from their company’s annual “w00tcamp” was this festive and versatile 16×16 pixel mega display.

From the sound of it, [GuuzG] and his mates at q42.com are not exactly hardware types, but they came up with a nice build nonetheless. Their design was based on 16 WS2812 LED strips for a 256 pixel display. An MDF frame was whipped up with cross-lap joints to form a square cell for each pixel. Painted white and topped with a frosted Plexiglass sheet, each RGB pixel has a soft, diffuse glow yet sharply defined borders. Powered by a pair of 5A DIN rail DC supplies and controlled by a Raspberry Pi, the finished display is very versatile – users can draw random pixel art, play the Game of Life, or just upload an image. [GuuzG] and company are planning to add Tetris, naturally, and maybe a webcam for fun.

We’ve seen lots of uses for the ubiquitous WS2812 LEDs, from clocks to Ambilight clones to ground-effect lighting for an electric skateboard. But if you’re in the mood for a display that doesn’t use LEDs, there’s always this multithreading display.

[via Reddit]

Finally, An Official Display For The Raspberry Pi

September 8, 2015 by Brian Benchoff 38 Comments

Yes, finally, and after years of work and countless people complaining on forums, there is a proper, official display for the Raspberry Pi.

It’s a 7-inch display, 800 x 480 pixel resolution, 24-bit color, and has 10-point multitouch. Drivers for the display are already available with a simple call of sudo apt-get update, and the display itself is available at Newark, the Pi Store (sold out) and Element14. There’s even a case available, and a stand ready to be sent off to a 3D printer.

As for why it took so long for the Raspberry Pi foundation to introduce an official display for the Pi, the answer should not be surprising for any engineer. It’s EMC, or electromagnetic compliance. The DPI (Display Parallel Interface) for the Pi, presented on the expansion header and used by the GertVGA adapter allows any Pi to drive two displays at 1920 x 1024, 60FPS. This DPI interface is an electrical nightmare that spews RF interference everywhere it goes.

The new display could have used the DSI (Display Serial Interface) adapter, or the small connector on the Pi that is not the camera connector. DSI displays are purpose-built for specific devices, though, and aren’t something that would or should be used in a device that will be manufactured for years to come. The best solution, and the design the Raspberry Pi foundation chose to go with, is a DPI display and an adapter that converts the Pi’s DSI output to something the display can understand.

The solution the Pi foundation eventually settled on is an adapter board that converts the DSI bus to DPI signalling. This of course requires an extra PCB, and the Foundation provided mounting holes so a Pi can connect directly to it.

While this is the first display to make use of the DSI interface, it will assuredly not be the last. The Pi Foundation has given us a way to use the DSI connector to drive cheap DPI displays. While the 800×480 resolution of the official display may be a bit small, there will undoubtedly be a few hardcore tinkerers out there that will take this adapter board and repurpose it for larger displays.

[Alex Eames] got his hands on the Pi Display a few weeks ago, you can check out his introductory video below.

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Monitoring Power With A 555

June 7, 2015 by Brian Benchoff 12 Comments

[Diederich] is running a Raspberry Pi loaded up with Pimatic, a great home automation server that does just about anything you can throw at it. One thing it doesn’t do is monitor electricity and gas directly from the meter – you’re going to need hardware for that. [Diederich] stepped up to the plate and built that hardware using just a 555 timer. The total cost of adding this to his Pimatic setup was less than a dollar.

The 555 can be used as a timer, a trigger, and a bunch of them can be cobbled together into a CPU. [Diederich] isn’t using some fancy logic here; he’s just using the 555 as a Schmitt trigger with a phototransistor and his electricity meter. The output of the 555 is connected to the GPIO of the Raspberry Pi, and a Python script ties into Pimatic.

It’s a neat solution that only costs a dollar, and using the 555 has a few advantages: the 555 makes it possible to use long and thin wires back to the Pi, which means [Diederich]’s Pi doesn’t have to be located right next to his meter.