Revision 2.0
------------
switched from GTK+ 2 to GTK+ 3
switched from parallel port to FTDI232R (USB to serial/bitbang)

LED  DBUS  FTDI232R
---  ----  --------
 0     0     30
 1     1      2
 2     2     32
 3     3      8
 4     4     31
 5     5      6
 6     6      7
 7     7      3

Revision 1.0
------------
shows 8 colored LEDs on screen
blink frequency and duty cycle can be set for each LED

uses GTK+ 2

controls 8 LEDs attached to parallel port

LED  BIT D-SUB 25
---  --- --------
 0    0     2
 1    1     3
 2    2     4
 3    3     5
 4    4     6
 5    5     7
 6    6     8
 7    7     9