DStarLet is a web-based text messaging application using D-Star digital data technology. Features:
One "master/server" computer is connected to the radio via a serial port.
A web browser on the "server" computer (as well as optional multiple "client" computers on a local network) is
used to perform all functions:
Multiple browser windows on the same or multiple computers can be used to create, send, receive, and manage
multiple messages in parallel.
The status of all incoming and outgoing messages are displayed in any browser window on any computer.
Messages can be printed on any computer using the browser's normal printing function.
A communications log of all messages sent/received can be viewed on any browser.
D-Star communications are performed in a Java servlet running in the background on the server, independent of any
browser.
Communications are error-free due to the use of a 32-bit CRC and an acknowledge/retry protocol.
Each incoming and outgoing message is automatically saved as an ordinary XML text file on the server computer.
Web pages are written in standard HTML, and thus are easy to customize without the danger of corrupting the Java
servlet communication logic (which runs on the server). Each HTML web page file contains a tiny amount of servlet
interface code (clearly marked) to communicate with the servlet.
"Master/server" computer requirements:
Hardware:
Pentium 233 or equivalent.
96MB RAM.
100MB available disk space (for Tomcat & the JDK).
An Ethernet network card, if client computers are also used.
An available serial port.
Software:
One of the following:
Windows 98 or higher.
Recent Linux/Unix.
Apple Mac OS 10.1 or later.
Apache's Tomcat web server (free),
version 5.5.10 or later, installed.
Sun Microsystems' Java JDK (Java
Development Kit, free), version 1.5 or later, installed.
Sun Microsystems'
JavaComm (Java Communications package, free), version 2.0 or later, installed.
"Client" computer requirements:
An Ethernet network card.
Any operating system (e.g., Windows, Linux, Mac OS) that supports network connections.
Any browser (e.g., Internet Explorer, Netscape, Firefox, Opera).
No other software (e.g., Java) needs to be installed on the client.
Advantages over other ARES/RACES messaging software:
The composition of multiple messages can be made in parallel in multiple browser windows, eliminating the need to
save one message being composed, in order to work on another one.
Messages can be created as a draft by one person, and then reviewed and sent by another person on another computer.
Incoming messages require a separate step to mark them as "received". This feature ensures that incoming messages
are not forgotten.
Since the entire program is open source,
maintenance and/or upgrades are not dependent on any relationship to the author.
Installation & configuration steps for the Java servlet:
Download & install Sun Microsystems' Java JDK
(Java Development Kit), v1.5.0 or later; all you need to install is the "Development Tools", and not the included JRE.
If you are running Windows NT 4, Windows 2000, or Windows XP, you can install the Sun Java JRE (Java Runtime Environment)
v1.5.0 instead.
Download & install Sun Microsystems'
JavaComm (Java Communications
package), v2.0 or later. Note: Sun has released version 3.0 for Solaris/Linux, but not for Windows. Here is
JavaComm 2.0 for Windows. If you
unzip the .ZIP file into your Java JRE installation directory, that should create a notes folder with some Sun
documentation, and also place the following files in the correct folders. Verify that the following files are correctly
installed (folders are relative to the Java JRE installation directory):
win32com.dll should be copied to: bin.
javax.comm.properties should be copied to: lib.
comm.jar should be copied to: lib\ext.
Download & install Apache's Tomcat
web server, v5.5.10 or later (or another suitable web/servlet server) on the same computer on which you installed Java.
Configure Tomcat as follows (all directory references are relative to the Tomcat base directory):
For those running Windows NT 4, 2000, or XP, installing the "core" version using the "Windows Service Installer":
Follow the installation instructions; the defaults ishould be OK for most installations.
For those running Windows NT 4, 2000, or XP, installing the "core" version from the .ZIP file:
Read the RUNNING.txt file.
Edit the conf\tomcat-users.xml file, replacing the <user ... > with:
SET JAVA_HOME=the path where you installed Java
SET CATALINA_HOME=the path where you installed Tomcat
Create shortcuts on your desktop, start menu, or elsewhere to bin\startup.bat
& bin\shutdown.bat.
Open the "Properties" of those shortcuts:
Select the "Memory" tab; set the "Initial Environment" to 4096.
Select the "Program" tab; check the "Close on exit" box.
You will use the above shortcuts to start & stop Tomcat.
Start Tomcat using the shortcut you created above (it may take 10–15 seconds to start).
Start your web browser and create a bookmark to http://localhost:8080/manager/html; this is the web page
for the Tomcat "Manager" web page used to install Java Servlet applications.
Download the DStarLet.war file
& deploy it into Tomcat using the "Manager" web page.
Start your web browser and create a bookmark to http://localhost:8080/DStarLet/; this is the web page
address for DStarLet. The first time you browse to each DStarLet web page after installing
or replacing the DStarLet.war file, Tomcat has to "compile" the web page (this may take 3–5 seconds),
but subsequent accesses should be quick. The first time you browse to the DStarLet main page,
it will take you to a configuration web page where you must enter at least the following parameters:
StationId. This should be set to the callsign (and optional SSID) of your station.
MessagePath. This is the name of the directory where you wish messages to be stored.
You can change the other values if necessary. To protect against unwanted changes to the configuration, the link
to the configuration page is password-protected using the username & password you set up in Tomcat for the
"Manager" role.
On Tomcat, if you want DStarLet to be the main web server page (instead of the Tomcat main
web page), in the Tomcat installation directory, move webapps/DStarLet/index.html to webapps/ROOT/;
then you can start DStarLet at: http://localhost:8080/. You can still get to the
Tomcat main web page at http://localhost:8080/index.jsp.
Note that the servlet logic is in a .JAR (Java Archive) file and thus separated from the .JSP
(Java Server Page) files used for interfacing the web pages to the servlet. The .JSP files contain normal
HMTL interspersed with Java servlet interface code. The Java servlet interface code in the .JSP files is
enclosed in <% & %>; avoid modifying the Java servlet interface code. This separation
of functions allows for users familiar with HTML to reformat or add to the layout of the web pages without risking damage
to the functioning of the program.
So you need additional fields on the message form? No problem; just edit the Message.jsp file. Decide on an
internal field name, add a default value for the internal field name in the Java code near the top of the file, and then
create an HTML <input> field. Use the same pattern that is used for the rest of the input fields.
Note that the servlet is designed to support multiple users composing and/or reading messages at the same time in multiple
windows, on the same or different computers, browsing to the web server machine. Further, you do not need to leave a
browser window open to receive messages. Operation of the servlet and web pages should be obvious. If at any time
starting the servlet does not work (by clicking on the main page's Start button), stop and restart D-Star.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
