Welcome to my light switching device project (LSD)

I have build a computer-programmable light switcher a few years ago.

In our scouting-group we had a light show that was really limited, a few programs and selectable speed. The major problem was the thick cable connecting the controller with the lights, always too short and difficult to handle.

So I developed an alternative controller based on a computer, connected with a standard telephone twisted-pair cable that worked very well: only 4 wires are needed (Data, Clock, Ground and VCC (5V)).

The hardware is connected trough the parallel port, but data is transmitted serially.

If you want to build it feel free, but you do it at your own risk!

 

This is the (simplified) circuit I used :

This is the serial data format

it is composed of a leading 1, 5 address bits and 8 data bits. Thus up to 40 lights at groups of 8 can be individually controlled.

On this page you can see an animation that explains the function of the circuit

Here you can find the complete circuit as I build it.

And here a list of all components used.

This data packet is clocked trough the shift-registers until the leading 1 is used as a trigger to compare the address field.

 

The original software was written in turbo pascal and ran under DOS. You can download it here (source-code and binary).. This program run's on the oldest hardware... (for example on an olivetti 8088 or a compaq portable III!).

 

You can download also a never control software written in visual basic, you can define your own programs, select the speed, random program. I have also implemented sound-control with a kind of FFT analysis and a pseudo-Vu-meter (using the FFT.DLL of Murphy McCauley).

This program can be downloaded here . It's the zipped source-code and the compiled binary

Since windows or visual basic has no low-level direct parallel port access I have used WinIO from http://www.internals.com. You'll need to copy the winio.* files to the windows directory to make it work. The files are included in the archive, but be aware that this is no complete installation, I have not included COMXTL32.OCX, COMDLG32.OCX, MSFLXGRD.OCX and MSVBVM60.DLL.
If you don't have those files already on your PC the program won't work (feel free to email me if you need them).

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