linux

678 Articles

Data Broacasting “Transparency Grenade” Ads Whimsy To Your Meetings

February 21, 2012 by 11 Comments

If you’re tired of underhanded deals going down behind closed doors maybe you need to start carrying around this transparency grenade. The enclosure is modeled after a Soviet-era F1 Hand Grenade. But it’s not filled with explosives and won’t send deadly shrapnel around the room. Instead, when the pin is pulled it starts recording audio and sniffing network packets, then broadcasts both to a remote server. Perhaps you could consider this to be data shrapnel sent around the world.

The exploded parts image above shows what hardware is at use. There’s a Gumstix board at the heart of the device which uses a WiFi module for sniffing and broadcasting data. The LED bar graph which you see in the fully assembled unit shows the wireless signal strength.

It sounds like the enclosure itself was 3D printed from Tusk2700T translucent resin but we’re a little confused by this part of the hardware description. We don’t have much of a need to transmit recordings of our meetings, but we’d love to use this case design for that MP3 enclosure.

[via Reddit]

Who Couldn’t Use A Little More Screen Space?

February 21, 2012 by 23 Comments

Text LCD’s are handy for any occasion, a printer port on your PC is also darn handy as well. Mix together and add in a splash of linux and you get a very handy Linux device driver for a 16×2 LCD connected to the parallel port.

Electrically the LCD is wired up in a typical 4 bit mode, this allows the parallel port to use its 8 bit data register to write data, but also control the Register Select and Enable pins. Next is to make a module for linux to use, it seems like pretty standard fair for this type of screen.

Make the driver, insert the module so it can be loaded, and add a node so you know where to find it later, and your only an “echo Hello > /dev/my_lcd” away from finding all sorts of creative uses for your new external display.

Raspberry Pi Runs XBMC; Reliably Decodes 1080p

January 24, 2012 by 62 Comments

This is the Raspberry Pi board, an ARM based GNU-Linux computer. We’ve heard a little bit about it, but it recently garnered our attention when the machine was shown running XBMC at 1080p. That’s a lot of decoding to be done with the small package, and it’s taken care of at the hardware level.

Regular readers will know we’re fans of the XBMC project and have been looking for a small form factor that can be stuck on the back of a television. We had hoped it would be the BeagleBaord but that never really came to fruition. But this really looks like it has potential, and with a price tag of $35 (that’s for the larger 256MB RAM option) it’s a no-brainer.

Now there’s still a lot of rumors out there. We came across one thread that speculated the device will not decode video formats other than h.264 very well since it uses hardware decoding for that codec only. We’ll reserve judgement until there’s more reliable info. But you can dig through this forum thread where the XMBC dev who’s been working with the hardware is participating in the discussion.

Don’t forget to peek at the demo clip after the break too.

Continue reading “Raspberry Pi Runs XBMC; Reliably Decodes 1080p” →

Computing With The Command Line

January 20, 2012 by 40 Comments

Here’s something we thought we would never see: computing with just pipes, /dev/zero, and /dev/null.

As a thought experiment, [Linus] imagined a null byte represented an electron. /dev/zero would have an infinite supply of electrons and /dev/null would make a wonderful positive power supply. With a very short program (named mosfet.c), [Linus] can use Linux pipes to control the flow of electrons between /zero and /null. [Linus] used mosfet.c with a very short shell script to create a NAND gate. From there all bets were off. He ended up creating a D flip-flop, 4-bit adder and a counter.

From a bit of cursory research, Linux has a maximum pipe capacity of 1,048,576 bytes and the maximum number of PIDs is 4,194,304 (correct us if we’re wrong). [Linus]  can theoretically build some of the classic CPUs of the 70s and 80s with his pipe logic. An Intel 486 is just out of reach, though. If you give someone a NAND or a NOR they’ll eventually build a computer; we thought we’d never see this, though.

Complete Guide To Compiling OpenWRT

January 19, 2012 by 9 Comments

Regular reader [MS3FGX] recently wrote a guide to compiling OpenWRT from source. You may be wondering why directions for compiling an open source program warrant this kind of attention. The size and scope of the package make it difficult to traverse the options available to you at each point in the process, but [MS3FGX] adds clarity by discussion as much as possible along the way.

OpenWRT is an open source alternative firmware package that runs on may routers. It started as a way to unlock the potential of the Linksys WRT54G. But the versatility of the user interface, and the accessibility of the Linux kernel made it a must-have for any router. This is part of what has complicated the build process. There are many different architectures supported and you’ve got to configure the package to build for your specific hardware (or risk a bad firmware flash!).

You’ll need some hefty hardware to ease the processing time. The source package is about 300 MB but after compilation the disk usage will reach into the Gigabyte range. [MS3FGX] used a 6-core processor for compilation and it still took over 20 minutes for a bare-bones distribution. No wonder pre-built binaries are the only thing we’ve ever tried. But this is a good way to introduce yourself to the inner workings of the package and might make for a frustrating fun weekend project.

Simple Low Toner Workaround Squeezes Out A Few Extra Pages When Your Printer Refuses

November 22, 2011 by 88 Comments

low-ink-hacking

[Andrew] was getting ready to print out an assignment when his Samsung printer suddenly started blinking a red error light at him. Unable to find any documentation explaining the issue, he called Samsung directly and found that it was indicating the toner cartridge was nearly empty.

He held down the button that prints a test page, which came out just fine despite the printer’s insistence that there was not enough toner left. Annoyed at the fact that he felt Samsung was trying to strong arm him into buying another pricey toner cartridge, he looked for a way around the restriction.

He discovered that his printer’s software allowed him to specify a custom test page document, though it required that the document be in PostScript format. After a few shell commands, he had his document converted and was on to bigger and better things.

While a bit time consuming, his workaround should let him get by on this toner cartridge at least for a little while longer. We imagine that since he’s using Linux, the process could probably be scripted to save time, though we’re not sure if the same can be said for Windows-based PCs.

NES Controller Is A Slick Way To Carry Around Your Portable OS

November 13, 2011 by 14 Comments

nes-controller-linux-drive

[Oliver] had an old NES controller laying around, and without any other use for it, he decided to repurpose it as a portable storage device.

He gutted most of the controller, removing the plastic standoffs, leaving the D-pad and remaining buttons intact. He crammed a 32 GB flash drive inside, along with the guts from an SD card reader. Using a Dremel he cut several openings into the controller, one for the flash drive and SD card reader’s USB ports, as well as for the SD card itself. When the physical modifications were finished, he installed a small Linux distro on the flash drive, which can be run by any PC that supports booting from USB.

While some might argue, we think it’s a neat way to reuse an old gaming peripheral that he might have otherwise thrown out. The portable OS is something that would certainly come in handy, though we can’t wait until the Raspberry Pi is finished – it would be awesome to have a complete computer packed in there too.