This document discusses serial communication hardware connections and the RxTx Java library. It begins by explaining serial communication hardware, including common connectors like DB-9 and the role of the UART. It then introduces the RxTx Java library, which provides serial communication capabilities for Java applications using native implementations. It discusses including the RxTx library in projects and provides an example of an applied project using RxTx for serial communication with an Arduino.

1. Java Library
Arkom Thaicharoen
THJUG

2. Agenda
• Hardware connection
• RxTx Java Library
• Applied Project

3. Hardware connection
• Serial communication is one of the ancient technologies in
computing that is still relevant today.
• Its origins date back to the 1960′s when serial communication
was used between teletypewriters and modems.
• Today, serial interfaces can be found inside myriads of
embedded systems where they transfer data between different
components.
This is a female "DB-9" connector A USB Series “A” plug

4. Hardware connection
• A serial link over UART(UART Universal Asynchronous
Receiver/Transmitter) consists of two connections for the transfer of
single bits.
• Each connection transmits bits in only one direction from the TX
(transmit) pin of one end point to the RX (receive) pin of the other end
point.
simplified block diagram of the UART:

5. Hardware connection
Table of the RS232-C signal assignments in the DB25 and DB9 connectors

6. Hardware connection

7. Hardware connection
• A serial interface is also a common way to connect a PC to
an embedded system.
• Application scenarios include firmware update,
logging/debugging, data streaming and many more.
Sensordrone Firmware Update Program

8. RxTx Java Library
What is RXTX?
• RXTX is a Java library, using a native implementation (via
JNI), providing serial and parallel communication for the
Java Development Toolkit (JDK).
• All deliverables are under the GNU LGPL license. It is based
on the specification for Sun's Java Communications API,
though while many of the class descriptions are the same
the package used it not, since gnu.io is used instead.
• A certain amount of compatibility is intended with API,
though this project should be considered as a fork and
therefore compatible in spirit, but not in implementation.

9. RxTx Java Library

10. RxTx Java Library

11. http://www.jcontrol.org/download/rxtx_en.html
RxTx Java Library

12. Include RXTXcomm.jar into your Library
RxTx Java Library

13. RxTx Windows Library RxTx Mac Library
RxTx Java Library

14. Applied Project
http://netbeans.dzone.com/nb-rs232-communication-plugin

15. Applied Project

16. Applied Project

17. Applied Project

18. Referent
• https://www.freebsd.org/doc/en_US.ISO8859-1/articles/serial-uart/
• http://www.6502.org/users/dieter/uart/uart_1.htm
• http://developer.sensordrone.com/support/sensordrone-firmware-update-program/
• http://users.frii.com/jarvi/rxtx/
• http://playground.arduino.cc/Interfacing/Java
• http://rxtx.qbang.org/wiki/index.php/Main_Page
• http://www.jcontrol.org/download/rxtx_en.html
• http://eclipsesource.com/blogs/2012/10/17/serial-communication-in-java-with-raspberry-pi-and-rxtx
• http://fizzed.com/oss/rxtx-for-java
• http://en.wikibooks.org/wiki/Serial_Programming/Serial_Java
• http://en.wikibooks.org/wiki/Serial_Programming/USB
• http://en.wikibooks.org/wiki/Serial_Programming/RS-232_Connections