# Jon's Binary Clock Applet

Copyright © 2000 by Telsa Gwynne

# Jon's Binary Clock Applet

`Jon's Binary Clock` applet, shown in Figure 1, shows the time in an unusual form: binary coded decimal. It has twenty-four LEDs which represent the hours, minutes and seconds by illuminating the appropriate LED. To add this applet to a Panel, right-click on the Panel and choose Panel->Add to panel->Applet->Clocks->JBC Binary Clock.

Figure 1. Jon's Binary Clock Applet

## Usage

You don't need to do anything special to this clock. It just sits there and flashes lights at you.

Right-clicking on the applet brings up a menu containing the following items:

- Help — displays this document.

- About… — shows basic information about `Jon's Binary Clock Applet`, inluding the applet's version and the author's name.

## Deciphering the Lights

BCD stands for binary-coded decimal, a way of representing normal denary (0,1,2,3,4,5,6,7,8,9) numbers as what programmers call "a set of binary numbers in four bits, thus removing the numbers A to F". If this doesn't make sense, just be aware that this clock is an amusement for programmers, and serves no really useful purpose.

It helps to read this clock upside-down! Start at the bottom and read up to the top.

The right-hand pair of columns shows the two digits of the seconds: the units on the right, the tens on the left. The centre pair of columns shows the two digits of the minutes. The left hand pair of columns shows the two digits of the hours.

You add up the values of the illuminated LEDs in each column. You should get a number between zero to nine for each. That's the time.

1. The bottom LED represents 1 when it is illuminated.

2. The next LED represents 2 when it is illuminated.

3. The next LED represents 4 when it is illuminated.

4. The top LED represents 8 when it is illuminated.

It is probably simplest to decipher the hours and minutes first before trying to follow the seconds, which are always changing.

As an example, we can read the time in Figure 1 in the section called Jon's Binary Clock Applet. Let's start with the hour. The first column has only 1 LED on, in the second lowest position, so this gives us "2" for the first digit of the hour. The second column has no LEDs on, so we have a "0" for the second digit of the hour. So the hour is "20", or 8PM for people who like AM/PM notation. Looking at the minutes, we have "0" for the first digit, and "1" for the second digit since only the bottom LED is lit. This gives us "20:01" so far. Lastly, we have the seconds. For the first digit, we have the lowest two LED's lit. These have value 1 (for the lowest) and 2 (second lowest) for a total of "3". And the second column of the seconds has the top LED lit, with a value of "8". Thus, the time is "20:01:38", or "8:01:38PM".

## Known Bugs and Limitations

If you add it to a vertical panel, it is a nice size. If you then move it to a horizonal panel, it changes size in the horizontal panel. If you move it back to a vertical panel, it doesn't change size back, and forces the panel to widen itself.

## Authors

`Jon's Binary Clock` was written by Jon Anhold (`<jon@snoopy.net>`. Please send all comments, suggestions, and bug reports to the GNOME bug tracking database. (Instructions for submitting bug reports can be found on-line. If you are using GNOME 1.1 or later, you can also use `Bug Report Tool` (bug-buddy), available in the Utilities submenu of Main Menu, for submitting bug reports.

This manual was written by Telsa Gwynne (`<hobbit@aloss.ukuu.org.uk>`). Please send all comments and suggestions regarding this manual to the GNOME Documentation Project by sending an email to `<docs@gnome.org>`. You can also submit comments online by using the GNOME Documentation Status Table.

## License

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.

A copy of the GNU General Public License is included as an appendix to the GNOME Users Guide. You may also obtain a copy of the GNU General Public License from the Free Software Foundation by visiting their Web site or by writing to

Free Software Foundation, Inc.
59 Temple Place - Suite 330
Boston, MA 02111-1307
USA