link on irq5 test

Interesting 31C3 Talks

Fri, 02 Jan 2015 23:55:00 +0000

The 31st Chaos Communication Congress (31C3) ended just 3 days ago, and there were several interesting talks.

They have got live streaming of the event over the web, as well as encourage you to use an external player with RTMP or HLS support. The video streams were very reliable and best of all, it’s available in HD. In comparison, I tried the Apple live event once and it was really crappy. For one, the HLS¹ URL is not publicly available , so someone had to dig that out and post it. Even after that, the audio stream was (I believe, unintentionally) a mix of both English and Chinese simultaneously.

The 31C3 video recordings were also uploaded very quickly after the event. This is much quicker than other events such as Black Hat (although as an attendee, you do get a copy of the stuff on a DVD). A really big kudos to the organizers and the video production team!

If you don’t have time to listen to each and every talk, here are a few selected talks that were interesting to me, as well as a short summary to see if it’s worth 30 or 60 minutes of your time.

A full list of talks can be found here: http://media.ccc.de/browse/congress/2014/index.html

Apple's Lightning Digital AV Adapter

Mon, 11 Mar 2013 22:39:00 +0000

Recently, Panic noticed the odd output resolution and MPEG-like artifacts with the new Lightning digital AV adapter and decided to take a hacksaw to it. They found an ARM processor inside. image credit: Panic blog Shortly after, they received an anonymous comment that explains it all: The reason why this adapter exists is because Lightning is simply not capable of streaming a “raw” HDMI signal across the cable. Lightning is a serial bus.

Reducing power usage on the iCufflinks' ATtiny4

Sat, 27 Aug 2011 14:24:00 +0000

I came across this very nice article which documents steps taken to reduce the power usage on the ATtiny4 used in the iCufflinks. The process managed to shave off about 315 μA, which boosts battery life quite a bit: The overall effect this has on the product is that the 24 hour time between battery changes can be upped to 38 hours. That is a pretty good power savings for the day.

Monica and the Switch

Sun, 24 Apr 2011 23:30:00 +0000

OMG I can be like that sometimes [youtube=http://youtube.com/watch?v=EFiPR5Gg9g4] [via the Dangerous Prototypes forum]

Apple's RAOP is Cracked

Mon, 11 Apr 2011 23:34:00 +0000

For a long time now, apps can stream high-quality audio to an Airport Express or an Apple TV using the RAOP protocol. However, the reverse cannot be done due to the fact that the protocol uses asymmetric encryption, which means the private key is baked into the firmware of the Apple (or Apple-licensed) device. Finally, someone has done something about it. James Laird dumped the ROM of his Airport Express and extracted the private key.

How Electret Microphones Work

Thu, 07 Apr 2011 18:39:00 +0000

There’s a really nice article on Open Music Labs that describe the inner workings of the ubiquitous electret microphone.

Fraudulent SSL Certs & Revocation

Thu, 24 Mar 2011 19:51:00 +0000

I just read news that fake SSL certificates were issued by Comodo CA, but more interestingly, browser updates were issued to blacklist the certificates. Why this was necessary since we already have a protocol for doing just that? I found out from this post on the torproject blog that talks about how OCSP is not properly implemented in browsers: The browsers treat revocation errors as soft errors and a MITM is deadly for revocation.

Filter Design in Thirty Seconds

Mon, 14 Feb 2011 18:02:00 +0000

If you want a working filter design fast, Texas Instruments has the document for you. http://focus.ti.com/lit/an/sloa093/sloa093.pdf High pass, low pass, band pass, band reject. Circuits for dual and single supply designs too.

Oscilloscope CRT disassembly and explanation

Sun, 06 Feb 2011 22:19:00 +0000

[youtube=http://youtube.com/watch?v=E55h2JCuCWk] Here’s a nice video about how an oscilloscope (or generally a regular) cathode ray tube works.

Prototyping Artwork

Fri, 09 Jul 2010 11:43:00 +0000

[Wikipedia: click for full size]

Photo Kiosks Infecting USB Devices

Wed, 07 Jul 2010 00:26:00 +0000

Here’s another reason why I think dedicated kiosks like these should never run Windows. … has Windows-based Fuji photo kiosks in at least some of its stores that don’t run antivirus software, and are therefore spreading infections… via customers’ USB storage devices. The same problem occurs with shared computers in our school’s lab computers - people come in with their thumbdrives and use it to save their files, but at the same time the virus on the drive autoruns.

Reverse-engineering the Clicker

Tue, 06 Jul 2010 16:51:00 +0000

A few semesters back, our school started trial runs to use these “clickers” as well. At that time I was thinking of cracking it open to see what makes it tick, as well as evil plans like trying to impersonate other clickers or sniffing what other people’s responses were. I only managed to peel back a bit of the plastic in front, but since the clicker was brand-new and I had to return it in a good condition, I didn’t dare to proceed any further than that.

7% Solution

Mon, 05 Jul 2010 00:02:00 +0000

This is an interesting read. I, too, just assumed the ±10% included the whole range and it would be of some random distribution. “Design your circuit to use values that lie 7% away from the nominal standard values, either higher or lower, and you’ll find plenty of those in the bins when you do your hand selection.”

How to take a screenshot

Sat, 05 Jun 2010 14:50:00 +0000

That’s it!