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Working with files on an external USB Hard-Drive

Posted by on Jun 1, 2013 in Hardware

I am the proud owner of an Apple Thunderbolt Display (2560×1440). It has an outstanding image quality, comes with built-in microphone, speakers, and autofocus FaceTime HD camera.
- Btw, the camera does a rather poor job with the white balance and has a red tint, but becomes useable with a tool like iGlasses 3 -

apple-11q3-thunderboltdisplay-rear-sm On the back, it has three USB -, one Firewire -, one Thunderbolt, and one Ethernet port. There is also this single bigger cable to the Laptop, combining Thunderbolt and power and keeping the desk neatly organized.

For a year or so, I have an external USB Harddrive (Western Digital 2 TerraBytes) connected to one of the display’s USB ports. I’m mainly using it for Time-Machine backups and storing application disk images etc. Since all cables disappear behind the display and not cluttering my desk, I never thought about connecting the harddrive straight to one of the Laptop’s USB ports directly. However, as it turns out, my nice and neat setup comes with quite a penalty.

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Sh!t We Like – TP-Link Nano Router TL-WR702N

Posted by on Jan 12, 2013 in Hardware

Pack your own parachute and bring your own wireless router

If you ever gave a talk or presentation that involved demonstrating software running on a wireless device, you probably remember some restlessness, approaching the venue.

What would the Wifi conditions be? Would you be able to connect your device(s) to the Wifi network? Would the bandwidth be sufficient, to support a smooth demo? etc. etc.

There is no such thing as perfect and you can never be over-prepared. The same it probably true when it come to display-adapters, especially if a MacBook is your presentation tool of choice. Pack all the Thunderbolt/MiniDisplayPort to DVI/HDMI/VGA adapters you can find. And just in case, I usually export my slides to PDF and put that file on a FAT-formatted USB-Thumb-drive. Moreover, I used to schlep a standard home-office router, together with its bulky power-supply of course. But not anymore …

I recently came across a nifty and tiny Wifi Router that is not only fast enough, but can be powered with a standard 5V phone charger, using a standard Micro-USB Cable – or even better, leeching power off a standard USB-Port (e.g., one of the MacBook’s USB-Ports).

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Streaming Your Webcam w/ Raspberry Pi

Posted by on Sep 8, 2012 in Embedded

[Last updated on Feb. 2. 2013 for (2012-12-16-wheezy-raspbian) Kernel Version 3.2.27+]

Three years ago, we bought two small Webcams and since we wanted to used them on Linux and OS X, we went with the UVC and Mac compatible Creative LIVE! CAM Video IM Ultra. This Webcam (Model VF0415) has a high-resolution sensor that lets you take 5.0-megapixel pictures and record videos at up to 1.3-megapixel, supported resolutions include 640×480, 1290×720, and 1280×960. If you like, you can go back and read what I was thinking about the IM Ultra back in 2009. Today, it’s not much used anymore, but may just be the right accessory for an Raspberry Pi.

With the USB Camera attached to the Raspi, lsusb returns something like this:

lsusb

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp.
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 004: ID 7392:7811 Edimax Technology Co., Ltd EW-7811Un 802.11n Wireless Adapter [Realtek RTL8188CUS]
Bus 001 Device 005: ID 041e:4071 Creative Technology, Ltd

Using the current Raspbian “wheezy” distribution (Kernel 3.2.27+), one can find the following related packages, ready for deployment:

  • luvcview, a camera viewer for UVC based webcams, which includes an mjpeg decoder and is able to save the video stream as an AVI file.
  • uvccapture, which can capture an image (JPEG) from a USB webcam at a specified interval

While these might be great tools, mpeg-streamer looks like a more complete, one-stop-shop kind-of solution.

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Raspberry Pi – Small Inexpensive Powerful

Posted by on Aug 1, 2012 in Hardware

Looks like Android 4.0 (aka Ice Cream Sandwich) is coming to the Raspberry Pi. But even without Android, the Raspbian OS (Debian Linux-based operating system optimized for the Raspberry Pi) turns this credit card sized computer into a powerful tool.

The single-board computer comes equipped with the Broadcom BCM2835 SoC (system on a chip, includes an ARM-11 700MHz processor, VideoCore IV GPU, and 256MB RAM.) While the computer does not have any Flash Memory on-board, the SDCard socket allows adding up to 64GB Flash Memory.
The HDMI video and audio support, Ethernet socket, and the two USB sockets, allow the device to be used as a mobile computing platform or embedded system. However, its complexity and lack of analog inputs will probably not make to many Arduino enthusiast jump ship just yet.
The size, price, available hardware features, combined with a Debian-based operating system make this board the perfect prototyping, learning, and teaching device for more than just basic computer science.

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Tiffany meets Android

Posted by on Oct 26, 2011 in Android

Ever since I started working on the Android platform and Android phone and tablet applications, I found it challenging to show my ideas, designs, and prototypes to a group of people, no matter how small that group was. Naturally, I wanted to not just explain concepts and behaviors but to show a live demo on a phone. However, the screen-size of a phone can be a serious obstacle when presenting to a small group. Moreover, the phone often gets covered by my hand when interacting with a mobile application.
I have tried to capture the phone’s screen with a video-camera and showing the live-view on a bigger monitor but reflections, glare, and insufficient lighting resulted almost always in an even worse experience and only in an controlled environment (light-box etc.), filming worked well and I was able to capture footage with a reasonable quality.

For the last couple of weeks now, we have started experimenting with USB-tethered Android screen capturing in combination with TiffanyScreens.

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