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6 Articles

Properly Pipe Laser Light Around With Homebrew Fiber Couplings

December 9, 2022 by 6 Comments

It’s a rare person who can pick up a cheap laser pointer and not wield it like a lightsaber or a phaser, complete with sound effects. There’s just something about the “pew-pew” factor that makes projecting a laser beam fun, even if it’s not the safest thing to do, or the most efficient way to the light from one place to another.

We suspect that [Les Wright] has pew-pewed his way through more than a few laser projects in his lab, including his latest experiments with fiber coupling of lasers. The video below is chock full of tips on connecting cheap communications-grade fiber assemblies, which despite their standardized terminations aren’t always easy to use with his collection of lasers. Part of the challenge is that the optical fiber inside the cladding is often very small — as few as 9 microns. That’s a small target to hit without some alignment help, which [Les] uses a range of hacks to accomplish.

The meat of the video demonstrates how to use a cheap fiber fault locator and a simple optical bench setup to precisely align any laser with an optical fiber. A pair of adjustable mirrors allow him to overlap the beams of the fault locator and the target laser precisely. The effects can be interesting; we had no idea comms-grade fiber could leak as much light through the cladding as this, and the bend-radius limits are pretty dramatically illustrated. [Les] teases some practical sensing applications for this in a follow-up video, which we’re looking forward to.

Looking for more laser fun with your remaining eye? Check out [Marco Reps] teardown of a 200-kW fiber laser.

Continue reading “Properly Pipe Laser Light Around With Homebrew Fiber Couplings” →

New Part Day: MEMS Loudspeakers

January 16, 2018 by 47 Comments

MEMS, or Micro ElectroMechanical Systems, are the enabling technology that brings us smartphones, quadcopters, tire pressure monitors, and a million other devices we take for granted today. At its most basic level, MEMS is simply machining away silicon wafers to make not electronic parts, but electromechanical parts. The microphone in your cell phone isn’t an electret mic you would find in an old brick phone from the 80s — it’s a carefully crafted bit of silicon, packed in epoxy, and hanging off a serial bus.

Despite the incredible success of MEMS technology, there is still something in your smartphone that’s built on 19th-century technology. Loudspeakers haven’t changed ever, and the speaker in your newest iThing is still a coil of wire and some sort of cone.

Now there’s finally a MEMS loudspeaker A company called USound has developed the first loudspeaker that isn’t just a bunch of wire and a magnet. This is a speaker built from a silicon wafer that can be as small as 3 mm square, and as thin as 1 mm. Since these speakers are built on silicon, you can also add an amp right onto the package. This is quite literally a speaker on a chip, and we’d bet that there are already engineers at Samsung looking at stuffing this into a flagship phone.

ST and USound announced these extraordinarily small speakers would actually be made, but so far it’s been just that — an announcement. This changed at CES where ST demonstrated VR goggles with multiple MEMS speakers. Does this mean MEMS speakers are on their way to Mouser and Digikey? We eagerly await the product announcement and demo dev board kit.

Atari Archaeology Without Digging Up Landfill Sites

August 27, 2016 by 14 Comments

We are fortunate to live in an age of commoditized high-power computer hardware and driver abstraction, in which most up-to-date computers have the ability to do more or less anything that requires keeping up with the attention of a human without breaking a sweat. Processors are very fast, memory is plentiful, and 3D graphics acceleration is both speedy and ubiquitous.

Thirty years ago it was a different matter on the desktop. Even the fastest processors of the day would struggle to perform on their own all the tasks demanded of them by a 1980s teenager who had gained a taste for arcade games. The manufacturers rose to this challenge by surrounding whichever CPU they had chosen with custom co-processors, ASICs that would take away the heavy lifting associated with 2D graphics acceleration, or audio and music synthesis.

One of the 1980s objects of computing desire was the Atari ST, featuring a Motorola 68000 processor, a then-astounding 512k of RAM, a GUI OS, high-res colour graphics, and 3.5″ floppy drive storage. Were you to open up the case of your ST you’d have found those ASICs we mentioned as being responsible for its impressive spec.

Jumping forward three decades, [Christian Zietz] found that there was frustratingly little information on the ST ASIC internal workings. Since a trove of backed-up data became available when Atari closed down he thought it would be worth digging through it to see what he could find. His write-up is a story of detective work in ancient OS and backup software archaeology, but it paid off as he found schematics for not only an ASIC from an unreleased Atari product but for the early ST ASICs he was looking for. He found hundreds of pages of schematics and timing diagrams which will surely take the efforts of many Atari enthusiasts to fully understand, and best of all he thinks there are more to be unlocked.

We’ve covered a lot of Atari stories over the years, but many of them have related to their other products such as the iconic 2600 console. We have brought you news of an open-source ST on an FPGA though, and more recently the restoration of an ST that had had a hard life. The title of this piece refers to the fate of Atari’s huge unsold stocks of 2600 console cartridges, such a disastrous marketing failure that unsold cartridges were taken to a New Mexico landfill site in 1983 and buried. We reported on the 2013 exhumation of these video gaming relics.

A tip of the hat to Hacker News for bringing this to our attention.

Atari ST image, Bill Bertram (CC-BY-2.5) via Wikimedia Commons.

OpenPLC Is Ready For Hacking

June 7, 2016 by 48 Comments

It’s been nearly four years since we covered [Thiago]’s OpenPLC project. He never stopped working on it, and now it’s in a highly polished state.

If you read our initial coverage of this project, it would be easy to assume that he just wanted to control some halloween decorations. He is actually a PhD student at the University of Alabama in Huntsville. His research topic is SCADA (aka Industrial Control Systems) cyber security. His goal was to find vulnerabilities in PLCs and, hopefully, fix them. However, no PLC manufacturer releases their source code, and he was having trouble getting a deep understanding of something so closed.

So, since no one was going to open their code and hardware for him he simply made his own. OpenPLC can be programmed in all 5 IEC 61131-3 languages: ST, IL, LADDER, FBD and SFC. On top of that, it lowers the barrier of entry to developing this kind of industrial hardware by being compatible with all the favorites Arduino, Raspberry Pi, Windows, Linux, etc.

“The OpenPLC is the first fully functional standardized open source PLC. We believe that opening the black-box of a PLC will create opportunities for people to study its concepts, create new technologies and share resources.”

New Part Day: STM32F7, An ARM Cortex-M7

June 26, 2015 by 62 Comments

It was announced last year, but ST is finally rolling out the STM32F7, the first microcontroller in production that is based on the ARM Cortex-M7.

The previous go-to part from the ST catalog was the STM32F4, an extremely powerful chip based on the ARM Cortex M4 processor. This chip was incredibly powerful in its time, and is still a respectable choice for any application that needs a lot of horsepower, but not a complete Linux system. We’ve seen the ~F4 chip pump out 800×600 VGA, drive a thermal imaging camera, and put OpenCV inside a webcam. Now there’s a new, even more powerful part on the market, and the mind reels thinking what might be possible.

Right now there a few STM32F7 parts out, both with speeds up to 216MHz, Flash between 512k and 1MB, and 320kB of RAM. Peripherals include Ethernet, USB OTG, SPDIF support, and I²S. The most advanced chip in the line includes a TFT LCD controller, and a crypto processor on-chip. All of the chips in the STM32F7 line are pin compatible with the STM32F4 line, with BGA and QFP packages available.

As with the introduction of all of ST’s microcontrollers, they’re rolling out a new Discovery board with this launch. It features Ethernet, a bunch of audio peripherals, USB OTG, apparently an Arduino-style pin layout, and a 4.3 inch, 480×272 pixel LCD with capacitive touch. When this is available through the normal distributors, it will sell for around $50. The chips themselves are already available from some of the usual distributors, for $17 to $20 in quantity one. That’s a chunk of change for a microcontroller, but the possibilities for what this can do are really only limited by an engineer’s imagination.

AlienFX

Simple Terminal Hack Is Fit For Hollywood

November 25, 2014 by 21 Comments

We’ve all seen the cheesy hacker scenes in movies and on TV. Three dimensional file system browsers, computer chip cityscapes, and other ridiculous visualizations to make the dull act of sitting at a keyboard look pretty on the silver screen. While real hackers know those things are often silly and impractical, sometimes we do go out of our way to pretty things up a bit.

Hollywood might be able to learn a thing or two from this latest hack. [Yuri] modified his Linux terminal to change the color of the back lights on his laptop’s keyboard. It’s the kind of thing that actually would look good in a modern hacker movie, and [Yuri] is living proof that it’s something that a real-life hacker would actually use!

[Yuri] has been running Simple Terminal. The Simple Terminal project aims to build a replacement for the default xterm program that removes all of the unnecessary features and simplifies the source code. It also aims to make your terminal experience prettier. Part of making things prettier means that you can choose the font color for your terminals, and of course each terminal window can have its own color if you so choose.

[Yuri] happens to own an Alienware laptop. This laptop comes with RGB LEDs behind the keyboard, allowing you to light them up just about any color you could ever want. [Yuri] thought it would be cool if his keyboard color matched the font color of his terminal windows. Thanks to AlienFX, he was able to write a simple patch for Simple Terminal that does exactly this. Now whenever he selects a terminal window, the keyboard automatically switches colors to match the text in that window. Be sure to check out the video below. Continue reading “Simple Terminal Hack Is Fit For Hollywood” →