Embedded Computers

Embedded computers are not just computer systems where you can input new programs, the embedded devices are preprogrammed. All you can do is make the most of the services that the embedded computer systems are capable of providing. Ever thought of how your digital camera or cell phone, or washing machine works? Sure they work with the support of electricity or may be they are battery powered but the functions that they execute is entirely because of the embedded systems.
Important features of embedded computers constitute:
The functions of the Embedded systems are not generic but rather specific.
In most cases Embedded computers are built in parts. Usually they constitute a single board or a chip placed inside the concerned machine that it must operate.
The software running the embedded computer systems is not stored in the disc drive but rather in the ROM. The software language used for writing the program is called FIRMWIRE.
Embedded Computers are capable of communicating with the world outside.
They do it with the help of peripherals. These peripherals comprise:

1.Universal Serial Bus (USB)

2.Synchronous Serial Communication Interface:
I2C, JTAG, SPI, SSC and ESSI

3.Discrete IO: aka General Purpose Input/Output (GPIO)

4.Networks: Controller Area Network, Lon Works, etc.

5.Serial Communication Interfaces (SCI): RS-232, RS-422, RS- 485 etc.,

6.Timers: PLL(s), Capture/Compare and Time Processing Units