The Electronics Hobbyist » Beginner

Arduino Serial Communication

Natalia — Wed, 04 Aug 2010 09:00:06 +0000

Computers can exchange bits of information serially (one after another, in sequence) or in parallel (several at the same time). In applications where it is necessary to have one computer talk to another, the most commonly used communication method is serial.

So it is no surprise that serial communication is the method used to send data between the Arduino board and a computer (or other device). Information is sent to and from the computer and the Arduino by setting a pin high or low. One side sets the pin and the other reads it.

The Arduino Duemilanove has one serial port that communicates on digital pins 0 (RX) and 1 (TX) as well as with the computer via USB. When you use the IDE to Upload your sketches to the Arduino, the bits are transmitted one at a time through the USB cable to the Arduino. The serial connection can also be used in our sketches to send data to the computer and to receive data from the computer via the serial monitor available on the IDE. This proves very useful for debugging your projects, as we will explore in the upcoming posts.

The Arduino serial library makes the following functions available for use in your sketches:

begin(): opens serial port and sets the rate for serial data transmission (the RX and TX pins cannot be used for general input and output when the serial port is being used)
end(): disables serial communication (this allows the RX and TX pins to be used for general input and output again)
int available(): gets the number of bytes stored in the serial receive buffer (the buffer holds 128 bytes) that are available for reading from the serial port
int read(): reads incoming serial data
flush(): flushes the serial receive buffer of incoming serial data
print(): prints data to the serial port as human-readable ASCII text
println(): prints data to the serial port as human-readable ASCII text followed by a carriage return character and a newline character
write(): writes binary data to the serial port

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An Arduino for Any Project

Natalia — Thu, 29 Apr 2010 09:35:56 +0000

The Arduino is based on the microcontrollers from Atmel. Here are current Arduinos available (the architecture is open source, and anyone can build their own “Arduino” based on the technical specs that are available for download from the official Arduino website).

Duemilanove: “Duemilanove” means 2009 in Italian and is named after the year of its release. The Duemilanove is the latest in a series of USB Arduino boards. It is based on the ATmega328 and has 14 digital input/output pins (of which 6 can be used as PWM outputs) and 6 analog inputs.
Mega: The Arduino Mega is based on the ATmega1280. It has 54 digital input/output pins (of which 14 can be used as PWM outputs) and 16 analog inputs.

Nano: The Arduino Nano is a small, breadboard-friendly board based on the ATmega328 (Arduino Nano 3.0) or ATmega168 (Arduino Nano 2.x). It has more or less the same functionality of the Arduino Duemilanove, but in a different package.
Bluetooth: The Arduino BT is an Arduino board with built-in bluetooth module, allowing for wireless communication. It features a surface-mounted ATmega168.
Lilypad: A stripped-down, circular Arduino board designed for stitching into clothing and other fabric/flexible applications. It can be sewn to fabric with conductive thread. Lilypads are available on versions based on the ATmega168 or the ATmega328.
Mini: The Arduino Mini is a small microcontroller board based on the ATmega168 (surface-mounted), intended for use on breadboards or when space is at a premium.

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Basic Hobby Electronics Vocabulary Part 4 of 4 (S-V)

Natalia — Mon, 25 Jan 2010 15:00:00 +0000

Schematic: A diagram of an electrical circuit that uses standardized symbols for the components.

Semiconductor: A material of electrical resistance between that of a conductor and an insulator. It is used to construct diodes, transistors, and integrated circuits.

Solder: A tin-lead alloy that becomes liquid when heated to above 360 degrees. It has low resistance, like other metals, and provides a strong mounting.

Switch: A device used to connect or disconnect the wires in an electric circuit, turning it on or off.

Transistor: A three-terminal, solid-state electronic device designed to amplify, oscillate, or switch the flow of current between two terminals.

Voltage: The measure of difference of electric potential across a material or between two points in a circuit.

Volts (V): The unit of measure for voltage.

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Basic Hobby Electronics Vocabulary Part 3 of 4 (I-R)

Natalia — Mon, 18 Jan 2010 15:00:00 +0000

Insulator: A material that has high electrical resistance and is therefore a poor conductor of electricity.

Integrated Circuit (IC): A type of digital circuit in which transistors, diodes, resistors and capacitors are constructed on a semiconductor base.

Light Emitting Diode (LED): A type of diode that generates light when current flows through it.

Ohm’s Law: The relationship between voltage, current and resistance.

Ohm (Ω): The unit of measure for resistance.

Printed Circuit Board (PCB): A board in which components are connected using a thin coat of conductive material “printed” on the board instead of wires. It is used for mounting electrical components.

Resistance: The electrical friction between an electric current and the material it is flowing through that causes electricity to be dissipated as heat.

Resistor: An electrical component used to introduce resistance into a circuit.

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Basic Hobby Electronics Vocabulary Part 2 of 4 (D-G)

Natalia — Mon, 11 Jan 2010 15:00:00 +0000

Digital Circuit: A circuit in which inputs and outputs have only two possible states: low (0) or high (1).

Diode: A two-terminal electronic device that allows current to flow in only one direction.

Direct Current (DC): Current that flows across a material in one direction only.

Disc Capacitor: A type of capacitor that has low capacitance and is used mostly in high frequency circuits. Disc capacitors are not polarized.

Electrolytic Capacitor: A type of capacitor that has high capacitance and is used mostly in low frequency circuits. Electrolytic capacitors are polarized.

Electronics: The science and technology concerned with and based on electricity and its applications.

Farad (F): The unit of measure for capacitance.

Ground: A common name for the reference point in an electrical circuit at which the measured voltage is taken to be zero.

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Basic Hobby Electronics Vocabulary Part 1 of 4 (A-C)

Natalia — Mon, 04 Jan 2010 15:00:00 +0000

If you’re a beginner to hobby electronics, here is a short list of the most basic terms you will encounter as you venture into your electronics hobby.

Alternating Current (AC): Current that is periodically reversing its direction of flow.

Ampere (A): The unit of measure for electric current. Commonly shortened to “amp”.

Battery: A device which uses a chemical reaction to convert chemical energy directly into electrical energy.

Capacitance: A measure of the electric charge that can be stored on a conductor; the ability of such conductors to store electric charge.

Capacitor: An electrical component that introduces capacitance in electric circuits.

Conductor: A material that has low electrical resistance and can therefore efficiently allow electrical current to flow through it.

Current: A measure of the flow of electric charge passing any point of a wire per unit of time.

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Starting Out on an Electronics Hobby – Resources

Natalia — Sat, 21 Nov 2009 03:13:00 +0000

Surround yourself with all things electronics:

Books: hobby electronics books on Amazon.com

Magazines:

Read up on electronics online:

Find good sources of electronics parts and components:

There are plenty of reliable electronics supplies stores online such as Parts Express, Jameco Electronics and Little Bird Electronics. Also check out local junk yards and flea markets, and last but not the least, ebay.

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Starting Out on an Electronics Hobby – Tools

Natalia — Thu, 05 Nov 2009 20:40:00 +0000

Whether your interest in an electronics hobby stems from the desire to build your own gadgets or to modify existing electronics devices so they perform better – or at least differently – it is important that you take the best approach possible in order to get the most enjoyment from your hobby.

When you are first starting out you should put together a kit of essential tools. A simple kit should have the following set of basic, good quality tools:

Wire cutter and stripper
Soldering iron and solder
Soldering iron stand (optional)
Desoldering tool (optional)
Pair of small pliers – long nose pliers
Screwdrivers – small straight type and medium cross point type
Test equipment – multimeter (optional)

If possible you should get a wooden board/bench to use as a dedicated work area.

For introductory courses on electronics as a hobby checkout the website below:
http://www.hobby-electronics.info/links/courses.php

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