Archive for May 2014

How LEDs are Made

Sparkfun has pretty interesting to look at article How LEDs are Made. How LEDs are Made factory tour article shows how LED supplier YunSun (Shenzhen China) makes LEDs. YunSun buys their LED dies from Taiwanese company (thin sheets contains thousands of LED dies). LED wire bonding machine attaches a hair-thin gold wire from the top

Friday Fun: Views on Finland

This Friday fun is about Finland, the country I live in. Finland, officially the Republic of Finland,  is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden to the west, Norway to the north, Russia to the east, and Estonia to the south across the Gulf of Finland.


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Internet of things news

Here are some resources to find latest news on Internet of Things (IoT): Business Insider magazine has quite interesting Internet of Things news section. VentureBeat has also Internet of Things news section. IoT News Network IoT News Alltop Internet of Things    

LED shield for Arduino

When testing with Arduino circuits, it is often useful to see digital signal states on different pins. It is easy to measure single signal pin state with multimeter, but when you want to monitor several pins visually you need something else. One useful option is to use LEDs connected to pins to show their state.

Rubics cube in your browser

Rubic’s Cube had it’s 40th Anniversary this week. Although the Rubik’s Cube reached its height of mainstream popularity in the 1980s (from where I remember it most), it is still widely known and used. Since then it’s sold over 350 million units, making it the best-selling toy ever. Rubik’s Cube is a hard task to

Arduino Ethernet Shield

The Arduino Ethernet Shield allows you to connects Arduino to your local LAN or Internet with Ethernet connection.. Just plug Arduino Ethernet Shield module onto your Arduino board, connect it to your network with an RJ45 cable. The original Arduino Ethernet Shield is based on the Wiznet W5100 Ethernet chip. Arduino IDE comes with example

Debugging and profiling in Linux

Here is a simple way to do post-mortem debugging for a program that crashes. First enable the saving of core files when program crashes by running the following command in shell before starting the program you want to test: ulimit -c unlimited When program crashes Linux creates core file named core to program running directory You