Arduino uno User Manual

communication from your application’s logic. Have a look at the project’s
examples to learn more about these features.
Ruby
Even dynamic languages such as Ruby give you instant access to your com-
puter’s serial port and to an Arduino connected to it. But before that, you
need to install the serialport gem:
maik> gem install serialport
Using it, you can connect to the Arduino in just 30 lines of code.
SerialProgramming/Ruby/analog_reader.rb
require 'rubygems'
Line 1
require 'serialport'
-
-
if ARGV.size != 1
-
puts "You have to pass the name of a serial port."
5
exit 1
-
end
-
-
port_name = ARGV[0]
-
baud_rate = 9600
10
data_bits = 8
-
stop_bits = 1
-
parity = SerialPort::NONE
-
-
arduino = SerialPort.new(
15
port_name,
-
baud_rate,
-
data_bits,
-
stop_bits,
-
parity
20
)
-
-
sleep 2
-
while true
-
arduino.write "a0\n"
25
sleep 0.01
-
line = arduino.gets.chomp
-
puts line
-
end
-
We create a new SerialPort object in line 15, passing it all the usual parameters.
After we sleep for two seconds, we start a loop and call write on the SerialPort
object. To get the result back from the Arduino, we call gets , and then we print
the result to the console. Here you can see the program in action:
Appendix 3. Advanced Serial Programming • 262
report erratum • discuss
www.it-ebooks.info

Arduino uno Specifications

General

Form factor	Arduino
Certification	RoHS, FC, CE
Processor model	-
Processor frequency	- MHz
Microcontroller model	ATmega328
Microcontroller frequency	16 MHz
DC input voltage	7-12 V
Operating voltage	5 V
DC current per I/O pin	40 mA
Flash memory	0.032 MB
Maximum internal memory	- GB
SRAM (Static Random Access Memory)	2 KB
EEPROM (Electrically Erasable Programmable Read-Only Memory)	1 KB
Wi-Fi	No
Number of analog I/O pins	6
Number of digital I/O pins	14

Weight and Dimensions

Board dimensions	53.4 x 68.6 mm