[David Donley] has wanted to make a LED matrix for a while now, and has decided to finally pull the trigger — after all, that many LEDs certainly aren’t cheap!
He’s using a set of 16 Adafruit 8×8 NeoPixel LED Matrices (almost $600 worth of LEDs) and a BeagleBone Black to control them. To mount the LED matrices he bought a sheet of 6061-T6 aluminum for two purposes — one to act as a giant heatsink, and two, to look cool. All he had to do was drill some holes in the sheet for the connectors, and then use 3M 300LSE double-sided adhesive to stick the NeoPixels to the surface. The result is a border-less display that looks clean and professional.
To power the array he’s using a 5V 90A power supply — at full brightness these LEDs can consume around 325W, or 65A at 5V! Taking notes from the opensource LEDscape code on GitHub he’s made his own software to control the display — stick around after the break to see it in action.
Continue reading “Aluminum LED Matrix Looks Professionally Made”
The BeagleBone Black, with an impressive amount of computing power and a whole bunch of I/O, would make an impressive CNC controller, save for two shortcomings: The BBB isn’t in stock anywhere, and CNC capes are a little on the pricey side. [Marc Peltier] can’t do anything about finding a distributor that doesn’t have the BeagleBone on backorder for you, but he did come up with an adapter for the very popular RAMPS-FD 3D printer controller board (Forum, French, Here’s the Google translation matrix).
The RAMPS-FD is an extension of the RAMPS board and a shield for the Arduino Due. Both the Due and BBB work on 3.3 V, meaning controlling the RAMPS-FD is simply a matter of finding the correct wiring diagram and pin assignments on the BeagleBone. [Marc] solved this problem by using the settings from the BeBoPr cape and using the existing BeBoPr LinuxCNC configuration.
The end result of [Marc]‘s tinkering is something a lot like [Charles Steinkueler]‘s CNC capes for the BeagleBone Black we saw at the Midwest RepRap Fest. [Charles] isn’t selling his capes, but no one else seems to be selling BeagleBone Blacks, either.
Continue reading “BeagleBone Black + RAMPS”
8-bit microcontrollers are the standard for RepRap electronics, but eventually something better must come along. There has been a great deal of progress with ARM-based solutions, and of course a few of these made a showing at the Midwest RepRap Festival.
First up is [Mark Cooper], creator of Smoothieboard, the ultimate RepRap and CNC controller. It’s an ARM Cortex-M3 microcontroller with Ethernet, SD card, and up to five stepper drivers. It had a Kickstarter late last year and has just finished shipping all the rewards to the backers. In our video interview, [Mark] goes over the functions of Smoothieboard and tells us about some upcoming projects: the upcoming Smoothiepanel will feature a graphic LCD, SD card, rotary encoder and buttons, all controlled over USB by the Smoothieboard.
Next up is [Charles] with a whole bunch of CNC capes for the Beaglebone. By far the most impressive board was a huge I/O expander, motor driver, and everything controller for a Beaglebone featuring – get this – three parallel port interfaces. This was a one-off board costing thousands of dollars, but [Charles] did show off a few smaller and more practical boards for Beaglebone CNC control. Here’s a link to [Charles]‘ capes.
Continue reading “MRRF: ARM-Based CNC Controllers”
It’s been just over thirty years since the original Macintosh was released, and [hudson] over at NYC Resistor thought it would be a good time to put some old hardware to use. He had found an all-in-one Mac SE “on the side of a road” a while ago (where exactly are these roads, we wonder), and the recent diamond anniversary for the original mac platform convinced him to do some major hardware hacking.
Inspired by a six-year-old project from a NYC Resistor founder aptly named the 24th anniversary Mac, [hudson] decided to replace the old hardware with more powerful components – in this case, a BeagleBone Black. Unlike the earlier build, though, the original CRT would be salvaged; the analog board on the Mac SE has pins for video, hsync, vsync, and power.
To get a picture on the old CRT, [hudson] needed to write a software video card that used the BeagleBone’s PRU. The CRT isn’t exactly “modern” tech, and everything must be clocked at exactly 60.1 Hz lest the CRT emit a terrible buzzing sound.
With a software video card written for the old CRT, the BeagleBone becomes the new brains of this beige box. It runs all the classic Linux GUI apps including XEyes and XScreenSaver, although flying toasters might be out of the question. He also managed to load up the Hackaday retro site with xterm, making this one of the best ways to make an old Mac SE useful.
There are a million tutorials out there for building a robot with an Arduino or Raspberry Pi, but they all suffer from the same problem: neither the ‘duino nor the Raspi are fully integrated solutions that put all the hardware – battery connectors, I/O ports, and everything else on the same board. That’s the problem Rex, an ARM-powered robot controller, solves.
The specs for Rex include a 1GHz ARM Cortex-A8 with a Video SoC and DSP core, 512 MB of RAM, USB host port, support for a camera module, and 3.5mm jacks for stereo in and out. On top of that, there’s I2C expansion ports for a servo adapter and an input and output for a 6-12 V battery. Basically, the Rex is something akin to the Beaglebone Black with the hardware optimized for a robotic control system.
Because shipping an ARM board without any software would be rather dull, the guys behind Rex came up with Alphalem OS, a Linux distro that includes scripts, sample programs, and an API for interaction with I2C devices. Of course Rex will also run other robotics operating systems and the usual Debian/Ubuntu/Whathaveu distros.
It’s an impressive bit of hardware, capable of speech recognition, and machine vision tasks with OpenCV. Combine this with a whole bunch of servos, and Rex can easily become the brains of a nightmarish hexapod robot that responds to your voice and follows you around the room.
You can pick up a Rex over on the Kickstarter with delivery due sometime this summer.
We’ve seen FPGA dev boards out the wazoo—even some following the current trend of putting an FPGA and an ARM processor on a single board. Take one good idea and mix it in with a few million Linux/ARM boards already piling up on workbenches the world over and you get LOGi: an FPGA designed to plug into the Raspberry Pi and BeagleBone.
Both the Raspberry Pi and BeagleBone versions of the LOGi feature a Spartan 6 FPGA with 9152 logic cells, 16 DSP Slices, 576KB of RAM, and 96 I/O Pins. There’s also 256 MB of SDRAM and a SATA connector. The Kickstarter has a few demos for this board, namely a machine vision, Bitcoin mining (though don’t expect this board to make return-on-investment with mining), and an autonomous vehicle control demo. The LOGi’s hardware is comparable to the Papilio Pro, so potential projects may include generating NTSC video, adding a VGA out, and a few retrocomputer emulations via OpenCores.
For what this Kickstarter asks for the Pi or ‘Bone version of the LOGi—$89 USD for either—you’ll get a surprisingly capable FPGA dev board that’s a bit cheaper than comparable offerings. Sure, you won’t save any money buying a Pi and a LOGi, but if you have a few Raspberries lying about, you could do much worse for a starter FPGA board.
Thanks [hamster] for sending this one in.
For both the Raspberry Pi and BeagleBone Black, there’s a lot of GPIO access that happens the way normal Unix systems do – by moving files around. Yes, for most applications you really don’t need incredibly fast GPIO, but for the one time in a thousand you do, poking around /sysfs just won’t do.
[Chirag] was playing around with a BeagleBone and a quadrature encoder and found the usual methods of poking and prodding pins just wasn’t working. By connecting his scope to a pin that was toggled on and off with /sysfs he found – to his horror – the maximum speed of the BBB’s GPIO was around three and a half kilohertz. Something had to be done.
After finding an old Stack Overflow question, [Chirag] hit upon the solution of using /dev/mem to toggle his pins. A quick check with the scope revealed he was now toggling pins at 2.8 Megahertz, or just about a thousand times faster than before.