Arduino uno User Manual

First we import all the libraries we need, and we define a constant for the
maximum length of the lines we are going to read from the Arduino. Then we
define a main function.
After we’ve made sure that the name of a serial port was passed on the com-
mand line, we initialize a serial port in line 15. Then we sleep for two seconds
to give the Arduino some time to get ready. After that, we start a loop in line
23 where we constantly send the string “a0” to the Arduino. We check the
result of serialport_write , and if it was successful, we read the result sent by the
Arduino in line 27. Let’s compile our little program:
maik> gcc arduino-serial-lib.c analog_reader.c -o analog_reader
Determine what serial port your Arduino is connected to (mine is connected
to /dev/tty.usbmodem24321 ) and run the program like this:
maik> ./analog_reader /dev/tty.usbmodem24321
a0: 495
a0: 376
^C
Everything works as expected, and accessing a serial port using C isn’t that
difficult. To embed this code into a C++ program, you should wrap it in a
class named SerialPort or something similar.
Note that the arduino-serial library works on any POSIX-compatible system—in
other words, it won’t work on Windows.
Java
The Java platform standardizes a lot, and it also defines how to access a
serial port in the Java Communications API.
2
But the API is only a specification
that still has to be implemented. Unfortunately, there is no complete or even
perfect implementation available at the time of this writing.
For many years the RXTX project
3
provided a good implementation, but it
hasn’t been updated for a while now.
Oracle’s own implementation runs only on a few platforms, and the remaining
solutions are commercial products you have to pay for.
Fortunately, the jSSC (java-simple-serial-connector) project
4
comes to the
rescue. It doesn’t implement the Java Communications API, but it follows a
2. http://www.oracle.com/technetwork/java/index-jsp-141752.html
3. http://rxtx.qbang.org/
4. https://code.google.com/p/java-simple-serial-connector/
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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