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Microcontrollers
Microcontrollers can be thought of
as very small, inexpensive computers which may be programmed to control systems
such as cell phones, microwave ovens, toys, automotive systems, etc. by sensing input from the
real world and controlling those devices based on that input.
Most electronic devices you use today have a microcontroller in them of some form or another.
A typical household has upwards of 25 to 50 microcontrollers performing
embedded control
in numerous appliances and devices.
Microcontrollers are easy to use with simple sensors and output devices,
and they can communicate with desktop computers fairly simply as well.
They're very useful for when you're designing a simple interactive device that doesn't need the
full power of a desktop computer, but does need to be smaller or cheaper.
Arduino
The Arduino chip is an example of a
high level microcontroller used for rapid
prototyping.
Starting clockwise from the top center:
- Analog Reference pin (orange)
- Digital Ground (light green)
- Digital Pins 2-13 (green)
- Digital Pins 0-1/Serial In/Out - TX/RX (dark green) - These pins cannot be used for digital i/o (digitalRead and digitalWrite) if you are also using serial communication (e.g. Serial.begin).
- Reset Button - S1 (dark blue)
- In-circuit Serial Programmer (blue-green)
- Analog In Pins 0-5 (light blue)
- Power and Ground Pins (power: orange, grounds: light orange)
- External Power Supply In (9-12VDC) - X1 (pink)
- Toggles External Power and USB Power (place jumper on two pins closest to desired supply) - SV1 (purple)
- USB (used for uploading sketches to the board and for serial communication between the board and the computer; can be used to power the board) (yellow)
