LED Display FAQ

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Photos of the setup, the grey box + ciruit board = webcam

What is this?

This is a Skytronic Display, which can display 7x120 pixels.

Specs: 1000 x 109 x 45mm, 12Vac, 2500mA, 2.2kg, RS232

It can display 20 characters at the regular font size, or automatically uses a narrower font to display 24 if required.

How?

The website starts off by adding a message to a MySQL database into a queue. The display is connected to a PC running PC alongside the PHP Serial Class to write data to the serial port. As the machine does not actually have a serial port a USB -> RS232/Serial converter is used.

Overview:
Website -> Database -> Local Application -> USB -> RS232 -> Display -> Webcam -> Internets!

Why?

Err, not sure at the moment.

How Much?

The cost of displays like these vary a lot, I got mine for roughly £100/$200 from an online shop that was having a clearance, they tend to have them on ebay for a similar price.

Filtering?

Yes, there is a certain amount of filtering to remove messages based on keywords from the queue.

What character set can I use?

The majority of ASCII characters

HTML Tags?

The system does not support html tags, and are stripped from the message as they will not work. The colour tags can be used though which are shown on the first page.

Closing tags do NOT need to be used, ie no </CR> needed..

Where is it?

The display is currently on the wall in a flat in Bristol, UK

Why can I only send one message at once?

To keep the queue down, only one message is allowed in the queue per connection, once your message is displayed you can add another.

I missed my message, why??

Occasionally the webcam can loose sync and not display a message, although this is unlikely.

The message could also have been removed due to the filter or that you are sending non-standard characters.

Why such a long wait time?

The wait time can sometimes be fairly long, unfortunately this is usually down to demand, if there are more people adding messages, the wait is longer.

The speed of the webcam could update faster, displaying messages faster but this may increase the chance of missing messages and would increase server load.

There has now been a limit of 150 at a time applied to the queue, this will allow for a max of a 25 minute wait

FAKE PHOTOSHOP LOLS?

No I assure you this is live, it would probably take more time to write a fake image overlay program rather than do this :)

Random Stats

As of 17/05/2008:

Total countries seen in: 150

Average time on site: 1:21 minutes

Top 5 countries: USA, UK, Canada, Australia, France

Browsers: Firefox 90%, IE 7%

Webcam Impressions: 90 million+