6.Getting started tutorial of Raspberry Pi--what kind of device is it?

What can you do with it
 Juvtmall ( a company supply PCB PrototypingPCBA service and sell kinds of components, modules and so on) 

The big advantage of Raspberry Pi is that it doesn't have a fixed pattern.
You can use it to play video or browsing the web, also can "play with" it, learn how to use this motherboard to do something, Raspberry PI is a flexible platform that can be played as a toy, a tool or experiment platform.
.An ordinary computer
Raspberry PI is a computer that can also be used to install free software on the web.You can use it to deal with documents or tables when you can't connect to the network.
.Learning to programming
Raspberry PI is designed as a teaching tool to encourage young people to carry out various computer experiments, It installs the interpreter and compiler of various programming languages. For beginners, you can use MIT and Scratch Graphical programming language. If you want to start coding directly, consider using Python.
You can also use C language, Ruby. Java and Perl these various languages to develop program..
.Electronic project platform
Raspberry PI is a much smaller, cheaper, and more important feature than a regular computer, and that's it can be used as an experiment platform for electronic projects.

What kind of device is it
The main board
A. processor. Raspberry PI uses a processor like i phone 3G or kindle 2, so you can recognize its ability to handle raspberry PI is similar to the two devices.
This is a 32-bit piece on the system (Soc, System on a chip), main frequency 700MHz, ARM11 architecture. ARM chips have a variety of architectures,And each kind of architecture has different characteristics, and of course the price is different. Raspberry PI of type B installs 512M memory, type A is equipped with 256M memory.

B.SD card slot. There is no hard disk on the Pi, and all the data is saved on the SD card. It is recommended to have a shell, Because of the SD card, accidentally run into SD may damage SD card slot.

C. The USB interface. The Raspberry Pi of type B offers two USB ports and only one of them of type A. The USB port of the early Pi  can only output about 100mA current, but the new version can already provide a larger current that completely meet  USB2.0 standard requirements.

D. Ethernet interface.
Raspberry PI of type B provides A standard RJ45 Ethernet interface, type A not, but it can connect to the network through Ethernet adapter of an additional  installed USB interface. You can also use wireless LAN access to network.

E. HDMI interface.
The KDMI interface provides digital video and audio output, which can support 14 different resolutions. By using an external converter, the HDMI signal can convert a DVI (a number of display devices use it) signals. Composite signal (analog video signal through a yellow RCA terminal connection) or SCRAT (a standard of connecting video equipment in Europe) signal.

F. Status indicator light.
There are 5 leds on the main board, which can be used to display the working state of the system.

G.Analog audio output.
Raspberry PI provides a standard 3.5mm analog audio output jack for use high impedance audio equipment (if it has an active speaker).

H. Composite video output.
Composite video output hole is a standard RCA jack, which can output PAL or NTSC system or  video signal of NTSC. The video format has much lower resolution than the HAMI. If your monitor or electricity can support HDMI, use HDMI instead of using compound video output.

L. Power interface.
First, there is no power switch on Pi,  plugged in Micro USB on Power interface to supply power  (this Micro USB is only used for power supply and cannot be used as a normal USB port transmission data).This kind of interface is cheaper and easy to find the USB power adapter.
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