A Leslie Wong Blog

I’ve had a webcam serving live images using WebCam2000 running on my Macbook. I recently bought a new webcam, a Creative Live! Cam Chat HD (it was cheaper, $25, when I bought it August 2012). The previous webcam I was using, a Vivicam 3350B (I bought it on Woot! for $8.50 in 2005), didn’t have a Windows 7 driver and I was using Windows XP Mode and Windows Virtual PC - it was a little cumbersome.

When the Raspberry Pi was released, I thought it would be a great webcam server. I ordered one from Allied Electronics last July, but they never had stock. When Adafruit started selling them, I bought one.

After I acquired a compatible USB keyboard and dug up an Intellimouse Explorer 3.0, I started out with the 2012-09-18-wheezy-raspbian image. Googling found a Romanian site, BobTech, with an excellent tutorial for setting up a Raspberry Pi streaming webcam (English Google translation). Basically, the instructions just worked.

Later, I bought an Edimax EW-7811Un USB Adapter and with the current 2012-10-28-wheezy-raspbian image, WiFi was even easier to setup. The only change I made in the network setup was to give the Raspberry Pi a static IP address so I could find it. I edited wlan0 section in /etc/network/interfaces:

iface wlan0 inet static

address 192.168.1.115

netmask 255.255.255.0

gateway 192.168.1.1

nameserver 208.67.222.222

wpa-ssid “Skynet”

wpa-psk xxxxxxxxxxxxxx

I made a change to have MJPG-streamer serve a single image instead of a stream. Instead of using http://raspberrypi:8080/?action=stream, I used http://raspberrypi:8080/?action=snapshot. I use a script to reload the page every 10 seconds.  In mjpg-streamer.sh, I set FRAME_RATE=”15″ You really don’t see much action unless it’s windy.

Once the Raspberry Pi was setup, I used puTTY to connect to it, so I can start mjpg-streamer and do other things without having the Raspberry Pi connected to a monitor.

Today I purchased and downloaded Windows 8 Pro on my c. 2003 Shuttle SB51G computer. It has a Pentium 4 2.8 GHz CPU. At the end of February 2012, I was able to install the Windows 8 Consumer Preview on it. Last June, I tried installing the Windows 8 Release Preview, which didn’t work.

I started the upgrade purchase through the Microsoft site and one of the upgrade adviser warnings said that the NX bit needed to be enabled in the BIOS. I knew that my CPU (Northwood) didn’t have this feature which was also the reason the Windows 8 Consumer Preview wouldn’t install. I still completed the purchase knowing that I would use the license on another computer. The Windows 8 installation procedure went through like everything it was fine. It was, until the reboot:

The message on the reboot said, “Your PC needs to restart. Please hold down the power button.” This same message was displayed after several cold boot attempts. The error code, 0x0000005D, with the parameters 0x030F0207, 0x756E6547, 0x49656E69, 0x6C65746E, as far as I can find, refer to an incompatible CPU.

I think it would have been nicer on Microsoft’s part to say, before I plopped down $39.95, that Windows 8 wouldn’t work with my CPU. I can imagine this happening to a customer reading the hype about Windows 8 and trying the upgrade, paying for it and then getting a cryptic message. It seems to be Microsoft’s way of saying, “Tough luck, bub.”

I restored XP from an image, and my ancient computer is back to being a file server.

This is a SpikenzieLabs Solder : Time™ watch. It uses a a 4-digit 7-segment red LED display that displays the time for about four seconds when the “stem” is pushed in.

There is a CR2032 lithium battery for power, though there is a connection on the circuit board for a power supply. The display could be kept on continuously with a AC/DC power adapter if you wanted to use it as a desk clock (or you could carry around a large battery wired to the watch on your wrist).

The component count is very low – you can see all of them in the photo. The two ICs and the LED module are soldered directly to the board to keep a low profile. The build time for someone familiar with soldering is probably less than an hour. It took me a little longer because I tried to use a yellow LED display module that I ordered from Digi-Key but the digits did not light evenly. The SpikenzieLabs forum suggests that a higher voltage (<5v) might work but I didn't try it. I unsoldered the yellow module and used the red one.

You should note that this is a big ass watch. A woman's watch case might be 23-29mm in diameter while a men's watch case is normally 37-42mm. The Solder : Time case measures ~ 60.8mm (2.4 in). People will notice the Solder : Time on your wrist unless you are the size of Andre the Giant.

The kit sells for $29.95 (USD) but you can also buy an assembled watch for $39.95.

The new, improved version, the Solder : Time II™ watch uses the ATmega328P microcontroller and four 5×7 LED matrix modules so you can do even more stuff with it.

via SpaceRip

I built a pocket size USB charger using a MintyBoost 3.0 USB charger, a 3.7 v, 2600 mAh LiIon battery and a built-in LiIon battery charger in an Altoids Wintergreen Mints tin. It can be used to recharge a cell phone, iPod or other small USB rechargeable device.

I’ve had adafruit.com‘s MintyBoost 3.0 kit and USB LiIon/LiPoly charger (this is v1.1) for a while but I never put them together. I liked the size of the Altoids gum tin of the previous MintyBoost versions I have built but I wanted a little more charging capacity than 2 AA batteries could provide. I wanted a suitable battery and enclosure that didn’t compromise charging capacity and size.

Using ladyada’s calculations for battery power, I decided to use a 3.7v 2600 mAh LiIon battery.

The battery’s capacity:
MintyBoost mWh = 3.7V * 2600 mAh = 9620 mWh input

The amount of current it can provide:
Output mAh @ 5V = 9620 mWh / 5 * 80% = 1539 mAh output (80% is the conversion efficiency)

Number of iPhone 4S recharges = 1539 mAh / 1430 mAh (iPhone battery capacity) ~ 1.1

The MintyBoost kit requires the soldering of a few components to a circuit board. I also made two mods to the internal battery charger. With this version (1.1) of the adafruit LiIon battery charger, removing the resistor R4 and replacing it with a 1K ohm resistor allows the internal battery to be charged at 1000 mA.

The internal battery charger has connections for external status LEDs. I connected current limiting resistors between the board and LEDs, then mounted the LEDs in holes in the Altoids tin. The green LED indicates that the internal battery is charging and the yellow LED indicates a fully charged battery. (LiIon/LiPoly charging tutorial at Adafruit Learning System)

The battery and circuit boards are mounted in the Altoids tin with double sided foam tape. I made a miscalculation in the height of the LiIon charger taped to battery – the cover won’t close when the charging cable for the internal battery is attached.

To charge the internal battery, a USB Mini B plug supplies the power to the internal battery charger as in the photo above. To charge a device, a USB Standard A connector is used. There’s also enough room in the Altoids tin for storing an Apple 30-pin to USB Cable.

Below are charging test results with an iPhone 4S starting with battery at 49%:

Time (minutes)      Charge (%)
0:00                           49%
0:15                           58%
0:30                           66%
0:45                           75%
1:00                           83%
1:15                           89%
1:30                           93%
1:45                           96%
2:00                           97%

If you are interested in the MintyBoost design process: http://www.ladyada.net/make/mintyboost/process.html

I drove my Alfetta Sprint Veloce to the 2012 All Italian Car and Motorcycle Show. The informal show is sponsored by the Alfa Romeo Association for the benefit of the Alameda Special Olympics.

This year, my Sprint Veloce was joined by Chris Keen‘s red Alfetta GT, (see flickr photoset below) so there were four representatives of the Alfetta family, including a sedan and a GTV6. There were plenty of Alfa Romeos, Ferraris, Fiats, a few De Tomasos, a few Lamborghinis. a few Lancias and a few Maseratis. On the motorcycle front, there were many Aprilias, Ducatis, Moto Guzzis and Vespas.

(larger images in a slideshow on flickr.com)

Little City Market, 1400 Stockton St, San Francisco, CA