Java comm and basic stamp

Borna

Hello all,
I’m interested to have an external program written in Java, writes a byte to a serial port and have Basic Stamp listen for that. Once the byte is received, Stamp should perform a task based on that byte.
I’m looking to write that in Java using PC with Windows. I can’t find any example of Java writing to COM port. Can anyone suggest a good material, sample code that I use and expand? Also it seems that Sun/Oracle no longer support comm. APIs Programming in windows.

obrienm

Hi,
This post is propeller related - but the java communication API code targets any type of serial port.
I worked at Oracle for 5 years spanning Sun acquisition on an unrelated JSR-220/317. The API is not being worked on but it definitely is functional on Win32. I use it extensively to communicate to my Parallax propeller cores.
The official Oracle Communications API 3.0 page below only mentions non-Windows operating systems - but I can assure you that Java code running any 32 bit JVM on a windows machine from XP to Windows 7 64-bit works fine.
http://www.oracle.com/technetwork/java/index-jsp-141752.html



The standard javax.comm library originally developed for linux but extended for win32 up until 2004 works fine for me. The library will not work on a 64 bit JVM but I am able to control multiple quickstart boards simultaneously from a single java process after first reloading them all using propellent in an Ant script.

Follow the steps in my blog - quoted below.

 *  Prerequisites: 
*      Java Serial Support on Windows 
*      See "PC Serial Solution" for the Lego(TM) RCX Brick at the following URL at MIT  
*      - it explains how to get the SUN javax.comm API working on Windows (it is officially supported only on Solaris and Linux). 
*            http://llk.media.mit.edu/projects/cricket/doc/serial.shtml            
* *      SUN/Oracle Java Communications API 3.0 (1998-2004) 
*            http://www.oracle.com/technetwork/java/index-jsp-141752.html 
*      - copy comm.jar and javax.comm.properties to both yourJDK and JRE lib directories 
*      - copy win32com.dll to both your JDK and JRE bin directories - no need for a registration via regsvr32 
*      - in your IDE (IE: eclipse.org) project add a library reference to comm.jar to get your javax.comm java 

see http://javahardware.blogspot.com/2010/11/led-display-board-driven-by-javaxcomm.html
and the original posts
http://forums.parallax.com/showthread.php?119851-Writting-propeller-data-to-a-file-on-my-PC&p=879906&viewfull=1#post879906
http://forums.parallax.com/showthread.php?109333-HowTo-Single-host-computer-and-multiple-propeller-serial-comm-and-programming&p=775612&viewfull=1#post775612
http://forums.parallax.com/showthread.php?137636-Quickstart-Board-reboots-when-PC-GUI-program-starts-and-stops&p=1071154&viewfull=1#post1071154

Ant picks up extra verbosity from propellent

<project name="grid" default="reload.all">

<property name="spin.file" value="lcas_20120129_grid_f_input.spin"/>
<property name="EEPROM" value="/EEPROM"/>
<!--property name="EEPROM" value=""/-->
<target name="reload.all" description="reload entire grid">
	<antcall target="reload">		<param name="port" value="23"/>	</antcall>
	<antcall target="reload">		<param name="port" value="48"/>	</antcall>
	<antcall target="reload">  		<param name="port" value="47"/>	</antcall>
	<antcall target="reload">		<param name="port" value="46"/>	</antcall>
</target> 	 

<target name="reload">
  <apply executable="propellent">
	<arg value="/PORT"/>
	<arg value="comm${port}"/>
	<arg value="${EEPROM}"/>
	<fileset dir=".">
		<patternset>
			<include name="${spin.file}"/>
		</patternset>
	</fileset>
  </apply>
</target>
</project>

thank you
michael.f.obrien at eclipselink.org