Full Featured Security Lock Demonstration

[Arshad Pathan] let us know about his latest project, a modular code lock that can be adapted to many different situations.

The user interface is made up of a character LCD screen and a 3×4 keypad. For this example [Arshad] is using a stepper motor as the locking mechanism. When the board is first powered up it runs the stepper in one direction until receiving input from a limiting switch. In this way, the microcontroller calibrates itself to ensure the lock is in a known position. From there it waits for user input. An unlocked door can be locked at any time by pressing the * key. Unlocking requires entry of the correct password. And a password can be changed by entering 9999 (followed by the old password when prompted).

In the video after the break [Arshad] does a great job of demonstrating the various modes which he has programmed. This stands on its own, but we always love to have more details so we’ve asked if [Arshad] is willing to share a schematic and the source code. We’ll update this post if we hear back from him.

Update: [Arshad] sent in a couple of schematics which can be found after the break.

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PDF Redaction Still Not Working

facebook

Facebook’s internal valuation was revealed this week thanks to shoddy PDF redaction. Court documents from a settlement between Facebook and ConnectU showed that Facebook values itself at $3.7 billion, much less than the $15 billion that was speculated during the Microsoft investment. The AP uncovered this by cutting and pasting from the redacted court document. It’s the same thing we showed in our PDF redaction screencast last summer… and it will never cease to be funny.

[photo: Bryan Veloso]

Why I Hate Django

[youtube=http://www.youtube.com/watch?v=i6Fr65PFqfk]

[Cal Henderson] delivered a keynote titled Why I Hate Django at the first annual DjangoCon. Django is an open source BSD licensed web framework written in Python. Google has posted the keynote in its entirety to YouTube, which you can find embedded above. While the talk is humorous (and takes many jabs at Rails developers) it does provide insight into what makes a good web framework. [Cal] is Director of Engineering at Flickr and is an authority on how to make websites scale. He points out that most frameworks are designed to get projects off the ground quickly, but are lacking when it comes to building an even larger service. He talks about several things in Django that need work and improvements that could be made. It’s really an interesting look at what it takes to go big. Continue reading “Why I Hate Django”

IPod Integration For Factory Radios

saab

Most factory radios in cars don’t include a line in. alfaGato decided he wanted to integrate an iPod into his system, but wanted to maintain the factory functions. His Saab 9-3 came with GM’s OnStar system (not activated) which he thought would make a decent in road into the radio. His instructions should work for most radios with a factory cellphone integration option. He opened the radio and cut the traces for the phone input to get separate left and right channels. These were wired to the external CD changer input. He didn’t have the factory changer and the phone input also had amplification on the line that would interfere with the iPod. He designed a circuit with two possible inputs: iPod connector or AUX. The circuit is designed to mute the inputs if OnStar is activated. The circuitry is contained within a Saab factory phone mount with an iPod holder attached to it. Check out alfaGato’s blog dedicated to the project and our previous auxiliary input projects.

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