Arduino uno User Manual

byte currentByte = serialPort.readBytes(1)[0];
while (currentByte != NEWLINE) {
line[i++] = currentByte;
currentByte = serialPort.readBytes(1)[0];
}
return new String(line);
}
}
Although this program defines a class named AnalogReader , it’s not very object-
oriented. We only define it because everything in Java has to live in a class
context.
The main function implements the protocol for our Arduino sketch. First, we
make sure that the name of a serial port was set on the command line. Then
we use this name to initialize a new SerialPort object. To open the serial port,
we call the openPort method. After a two-second pause, we configure the serial
port’s parameters.
In the loop that follows, we send the string “a0” to the serial port using Serial-
Port ’s writeString method. Afterward, we read the result by invoking the readLine
function and print it to the console.
Currently, jSSC doesn’t offer a readLine function, so we have to write our
own. The function reads the Arduino’s response byte by byte using the readBytes
method, because jSSC doesn’t offer a method for reading a single byte. readLine
appends all bytes read to the byte array named line until it detects a newline
character (ASCII code 10). Finally, it converts the byte array into a String object
and returns it.
Here’s how to compile and use the program:
maik> javac -cp jssc.jar AnalogReader.java
maik> java -cp jssc.jar:. AnalogReader /dev/tty.usbmodem24321
a0: 496
a0: 433
a0: 328
a0: 328
^C
AnalogReader does exactly what it’s intended to do: it permanently prints the
values of the analog pin 0. Accessing a serial port in Java is a piece of cake
if you use the right libraries.
Note that jSSC also allows you to write object-oriented code. It has a Serial-
PortEventListener interface that makes it easy to decouple the handling of serial
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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