BeagleBone Pin-Toggling Torture Test

Benchmarks often get criticized for their inability to perfectly model the real-world situations that we’d like them to. So take what follows in the limited scope that it’s intended, and don’t read too much into it. [Joonas Pihlajamaa]’s experiments with toggling a hardware pin as fast as possible on different single-board computers can still show us something.

The take-home result won’t surprise anyone who’s worked with a single-board computer: the higher-level interfaces are simply slow compared to direct memory-mapped GPIO access. But really slow. We’re talking around 5 kHz from Python or any of the file-based interfaces to the pins versus 3 MHz for direct access. Worse, as you’d expect when a non-realtime operating system is in the middle, there are glitches on the order of ten milliseconds with all the file-based methods.

This test only tells us so much, though, and it’s not really taking advantage of the BeagleBone Black’s ace in the hole, the PRUs — onboard hardware processors that bring real-time IO capabilities to the system. We’d like to see a re-write of the code to take advantage of libpruio, for instance. A 20 MHz square wave is a piece of cake with the PRUs.

Of course, it’s not interacting, which is probably in the spirit of the benchmark as written. But if raw hardware speed on a BeagleBone is the goal, it’s likely that the PRUs are going to feature prominently in the solution.

BlinkenBone Meets The PiDP8

Years ago when the old mainframes made their way out of labs and into the waiting arms of storage closets and surplus stores, a lot got lost. The interesting bits – core memory boards and the like – were cool enough to be saved. Some iconic parts – blinkenlight panels – were stashed away by techs with a respect for our computing history.

For the last few years, [Jörg] has been making these blinkenlight panels work again with his BlinkenBone project. His work turns a BeagleBone into a control box for old console computers, simulating the old CPUs and circuits, allowing them to work like they did thirty years ago, just without the hundreds of pounds of steel and kilowatts of power. Now, [Jörg] has turned to a much smaller and newer blinkenlight panel, the PiDP-8.

The PiDP-8 is a modern, miniaturized reproduction of the classic PDP 8/I, crafted by [Oscar Vermeulen]. We’ve seen [Oscar]’s PiDP a few times over the last year, including a talk [Oscar] gave at last year’s Hackaday Supercon. Having a simulated interface to a replica computer may seem ridiculous, but it’s a great test case for the interface should any older and rarer blnkenlight panels come out of the woodwork.

SDR Cape for BeagleBone

In the old days if you wanted to listen to shortwave you had to turn a dial. Later, you might have been able to tap in a frequency with a keypad. With modern software-defined radio (and the right hardware) you can just listen to the entire high-frequency spectrum at one time. That’s the idea behind KiwiSDR, an open source daughterboard (ok, cape) for the BeagleBone.

The front end covers 10 kHz to 30 MHz and has a 14-bit converter operating at 65 MHz. There is a Xilinx Artix-7 A35 FPGA onboard and a GPS, too. The design is open source and on GitHub.

The interface uses the OpenWebRX project for a powerful HTML 5 interface. You can see a video of its operation below or, if you can get one of the four available slots, you can listen online. From a network point of view, the demo station in Canada worked best for us. However, there are also stations in New Zealand and Sweden.

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Hackaday Links: March 13, 2016

Way back in 2014, Heathkit was a mystery. We knew someone was trying to revive the brand, but that was about it. Adafruit pulled out all the stops to solve this mystery and came up with nothing. The only clue to the existence of Heathkit was a random person who found a geocache in Brooklyn Bridge Park. Since then, Heathkit has released an odd AM radio kit and $150 antenna. These offerings only present more mysteries, but at least [Paul] was finally rewarded for finding the Heathkit geocache. Heathkit sent [Paul] the AM radio kit. He says it’s neat and well documented.

[David] is doing his masters thesis on, “The motivation of the maker community”. That means empirical data, and that (usually) means surveymonkey. You can take his survey on the motivations of the maker community here.

America’s best loved companies, Verizon and Makerbot, together at last.

The BeagleBone Black was launched in 2013. The BeagleBone Green – a Seeed joint – showed up last August. The BeagleBone Blue, released just a few months ago, is a collaboration between the UCSD engineering department and TI. Now there’s the BeagleBone Enhanced. Yes, they should have picked another color. Perhaps ecru. The BB Enhanced sports one Gigabyte of RAM, Gigabit Ethernet, two USB ports and two USBs via an expansion header, optional serial NOR Flash for a bootloader, optional six-axis gyro, and optional barometer.

Atmel is changing a few AVRs. There is a new die for the ATMega 44, 88, 168, and the ‘Arduino chip’, the ATMega328. Most of the changes are relatively inconsequential – slightly higher current consumption in power save mode – but one of these changes is going to trip up a lot of people. The Device ID, also known as the source of the avrdude: initialization failed, rc=-1 error, has changed on a lot of chips.

Makeit Labs in Nashua, New Hampshire has a problem. They were awarded $250,000 in tax credits to help them move and renovate. Sounds like a very good problem, right? Not so: they need to sell these tax credits before the end of the month, or they lose them. They’re looking for a few businesses in New Hampshire to buy these tax credits. From [Peter Walsh]: “Under the credit program, a typical business donating $10,000 would save $9,000 on their state and federal taxes! That $10,000 donation would cost them only $1006!” Does that make sense? No, it’s taxes, of course not. If you’re a business in New Hampshire and are looking to reduce your tax burden, this is the solution.

So I mentioned MRRF, right? You should go to MRRF. It’s next weekend.

Back to the Drawing Board

Ever try signing your name with a mouse or a trackball? Not so easy. You could buy a graphics tablet with a pen. [Rahul Ramakrishnan] has a different approach. He took two 10-turn pots, and attached some strings and a washer. A pencil goes through the washer, and a BeagleBone Black reads the pots to determine what it is drawing on the paper. A couple of retractable badge lanyards keep tension on the string.

This ingenious design would be easy enough to replicate with any microcontroller that can read the two pots. The only awkward part is the need to press a button down when you want the device to treat the pencil as down (see the video below). It would probably be easy to rig up some switch on the pencil to make operation a little smoother.

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Shmoocon 2016: The Best Conference Booth You’ll Ever See

Shmoocon is here, and that means a dozen or so security companies have bought a booth and are out to promote themselves. Some are giving out shot glasses. One is giving out quadcopters. It is exceedingly difficult to stand out in the crowd.

At least one company figured it out. They’ve built a game so perfect for the computer literate crowd, so novel, and so interesting it guarantees a line in front of their booth. Who are they? Fortego, but that’s not important right now. The game they’ve created, BattleBits, is the perfect conference booth.

The game play for BattleBits is as simple as counting to two. You’re presented with an eight-bit hexidecimal number, and the goal is to key them into a controller with eight buttons for 1, 2, 4, 8, 16, 32, 64, and 128. The answer for 0x56 is 01010110, and the answer for 0xFF is mashing all the buttons.

BattleBits Screenshot

To anyone not familiar with hex, there’s actually a rather handy trick to the game: you only need to memorize 16 different numbers. Hexadecimal numbers are easily broken up into nibbles, or groups of four bits. All you need to do is solve one hexadecimal digit at a time.

The controllers, or ‘decks’ as they’re, are built around a BeagleBone and a custom cape running a mishmash of Javascript and Python. When the game starts the player or players are presented with random bytes in hexadecimal format. Input the right bits in the shortest amount of time and you’ll work your way up the leader board.

This is by far the best conference booth I’ve ever seen. The creator of the BattleBits hardware, [Riley Porter], says he’ll be releasing the design files and code for this game so anyone can make one, something we really look forward to.

[Riley] also got a video of someone entering nibbles super, super fast.

Introducing the BeagleBone Blue

The BeagleBone is a board that doesn’t get a lot of attention in a world of $5 Raspberry Pis, $8 single board computers based on router chipsets, and a dizzying array of Kickstarter projects promising Android and Linux on tiny credit card-sized single board computers. That doesn’t mean the BeagleBone still isn’t evolving, as evidenced by the recent announcement of the BeagleBone Blue.

The BeagleBone Blue is the latest board in the BeagleBone family, introduced last week at CES. The Blue is the result of a collaboration between UCSD Engineering and TI, and with that comes a BeagleBone built for one specific purpose: robotics and autonomous vehicles. With a suite of sensors very useful for robotics and a supported software stack ideal for robots and drones, the BeagleBone Blue is the perfect board for all kinds of robots.

On board the BeagleBone Blue is a 2 cell LiPo charger with cell balancing and a 6-16 V charger input. The board also comes with eight 6V servo outputs, four DC motor outputs and inputs for four quadrature encoders. Sensors include a nine axis IMU and barometer. Unlike all previous BeagleBones, the BeagleBone Blue also comes with wireless networking: 802.11bgn, Bluetooth 4.0 and BLE. USB 2.0 client and host ports are also included.

Like all of the recent BeagleBoards, including the recently released BeagleBone Green, the Blue uses the same AM3358 1 GHz ARM Cortex 8 CPU, features 512 MB of DDR3 RAM, 4GB of on board Flash, and features the main selling point of the BeagleBoard, two 32-bit programmable real-time units (PRUs) running at 200 MHz. The PRUs are what give the BeagleBone the ability to blink pins and control peripherals faster than any other single board Linux computer, and are extremely useful in robotics, the Blue’s target use.

Right now, the BeagleBone Blue isn’t available, although we do know you’ll be able to buy one this summer. Information on pricing and availability – as well as a few demos – will come in February.