The LED Script

Syntax

Each command must be on one line; they cannot be split onto multiple lines. No more than one command can be on a line. A line that starts with a "!!" is a comment. Here is an example of a script:

!! Just a simple script
Do
   !! Move "Hello" up onto the sign
   ScrollUp delay=30 center=true text=Hello
   Sleep delay=1000

   !! Scroll "This is a test" left onto the sign
   ScrollLeft delay=30 startspace=20 endspace=80 text=This is a test
   Sleep delay=300

!! Repeat infinitely
Repeat times=-1

The Options

The different options for each function/transition are as follows:

clear=true
delay=<non-neg int>
startspace=<non-neg int>
endspace=<non-neg int>
center=true
times=<-1 | non-neg int> (-1 specifies infinity)
pixels=<pos int>
text=<string>

The Functions/Transitions

The different functions/transitions available in LED Sign are as follows:

Appear - Cause text to appear on the sign
Sleep - A delay
ScrollUp - Scroll whatever is on the sign and the new message on going from bottom to top.
ScrollDown - Scroll whatever is on the sign and the new message on going from top to bottom.
ScrollLeft - Scroll whatever is on the sign and the new message on going from right to left.
ScrollRight - Scroll whatever is on the sign and the new message on going from left to right.
ScrollCenter - Scroll whatever is on the sign and the new message originating from the center.
OverUp - same as ScrollUp except it overwrites whatever is on the sign.
OverDown - same as ScrollDown except it overwrites whatever is on the sign.
OverLeft - same as ScrollLeft except it overwrites whatever is on the sign.
OverRight - same as ScrollRight except it overwrites whatever is on the sign.
OverCenter - same as ScrollCenter except it overwrites whatever is on the sign.
Pixel - Pixel in a new message
Blink - Cause what ever is on the sign to blink
Do - begin a "Repeat" block
Repeat - end a "Repeat" block
Reload - reload the script. Useful if information is updated frequently (like stock quotes). Probably the most powerful feature of LED Sign.

Usage

Appear [clear=true] [spacing] [text=<String>]
Sleep [delay=<non-neg int>] (defaults to 1000)
ScrollUp [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
ScrollDown [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
ScrollLeft [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
ScrollRight [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
ScrollCenter [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
OverUp [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
OverDown [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
OverLeft [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
OverRight [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
OverCenter [clear=true] [delay=<non-neg int>] [spacing] [text=<String>]
Pixel [clear=true] [delay=<non-neg int>] [pixels=<pos int>] [spacing] [text=<String>]
Blink [delay=<non-neg int>] [times=<pos int>]
Do (no parameters)
Repeat times=<-1 | non-neg int> (the "times" parameter is required)
Reload (no parameters)

[spacing] = [center=true] | [startspace=<non-neg int>] [endspace=<non-neg int>]

Text Color

In LED Sign you can make the "on" LEDs six different colors:

Red (default)
Orange
Yellow
Green
Blue
Purple

The way you specify a color is with a '\' followed by 'r', 'o', 'y', 'g', 'b' or 'p'. Everything after a color specification will be that color until another color is specified or the end of the message is reached. The text specified as: text=This \ois \ya \gtest will appear on the sign as "This is a test" but with "Test" being red, "is" being orange, "a" being yellow and "test" being green.

Notes

The "text" parameter must be the last parameter, because the string after the "test=" is your message. This makes it easy to parse (ie no nested quote problem) and easy for the user. What you see is what you get!!!

If the "clear=true" parameter is given to one of the transitions, it will cause the sign to clear (turn off LEDs) in the manner of the transition. i.e. "ScrollDown clear=true" would clear the sign by scrolling whatever is on the sign down off the sign.

If the "center=true" option is set, then the message will be centered on the sign if it fits on the sign. It doesn't make sense to center a message if it is longer than the sign. So, if your message isn't centering, then it is probably too long. The "startspace" and "endspace" parameters are ignored when the "center=true" parameter is given.

The script is much like HTML in how it handles function tags and parameters. It will ignore anything it does not recognize. However, there are some ways to stop the applet. For example, "delay=fifty" is incorrect because "delay" requires an integer and would thus cause the applet to stop. There is some script error output. If you are having trouble with LED Sign running your script, check your .hotjava/weblog; any error output is printed there.