LEDLightDistrict

Projects
Participants	Guido, Wizzup
Skills	soldering, coding
Status	Active
Niche	Electronics
Purpose	World domination

Project to LED'ify the outside facing glass 'block' wall. each glass box will be a pixel

Wall

As seen behind the blinds here. Better pics to come

Initial Plan

Create a 7 segment clock. User:amx109 is the owner and implementer of this project.

The clock will utilise 2 x TLC5940 to address 28 '7 segment' elements, spanning a grid of 21x7 blocks. The aim is to complete the clock by 16/05

Full LED addressable wall

Design A

Other Suggested Approaches

1

Cheap LEDs, TLC5940's

2

LED strip - addressable LED strip
http://www.ledsee.com/index.php?page=shop.product_details&flypage=flypage.tpl&product_id=720&category_id=209&option=com_virtuemart&Itemid=1&vmcchk=1&Itemid=1

or maybe

http://www.adafruit.com/index.php?main_page=product_info&cPath=37&products_id=285http://www.adafruit.com/index.php?main_page=product_info&cPath=37&products_id=306

or

http://www.adafruit.com/products/346

or

http://www.alibaba.com/product-gs/547114165/Newest_32pcs_5050_RGB_Versatile_LED.html

or

The one Antony brought in as Sample was bought: USD 1.21 @ volulmes 20 squares. http://www.aliexpress.com/fm-store/701799/209889132-519156534/20pcs-string-waterproof-led-pixel-module-4pcs-SMD-RGB-5050-1pcs-WS2801-256-gray-level-DC12V.html

Or

... big square pre-wired pixels: http://bliptronics.com/item.aspx?ItemID=88

We discussed mounting these in the corner of each brick at an angle so the light diffuses better. Need to experiment to see what works best.

The above LED strips/chains are easily controlled via an Arduino with the excellent FastSPI library: http://code.google.com/p/fastspi/

3

Some suggestions by Axel: http://www.nerdkits.com/videos/ledarray2/

http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1232748045

4

Shift register with pwm output

product number: 74595

HC595

5

Simulate a pwm based shift register

http://www.elcojacobs.com/shiftpwm/

6

http://francisshanahan.com/index.php/2009/how-to-build-a-8x8x3-led-matrix-with-pwm-using-an-arduino/

7

http://www.austriamicrosystems.com/led-driver/AS1130

A 132 channel led driver with pwm...

We could order samples. 3 samples per person, so if 3 people order a sample, we have sufficient channels...

And at 8$ they aren't that expensive either...

Though I might not understand what they do and they might be dissapointing...

8

These are bloody cheap though they are supposedly hard to program.

20$ per roll, and you have to buy 5 rolls minimum... but... 5m per roll, and... 40 color leds per m (from what I can tell). That means that we buy several screens, but in total it will still be cheaper. Strips can be cut per segment of two (studying the picture, correct me if I am wrong). This makes extending them relatively easy. We cut all wires to the appropriate length in one go. We have to connect some 150 of these strips, but it is repetitive work, so we can do it very fast.

http://www.alibaba.com/product-gs/529960769/_SMD5050_hl1606_rgb_led_strip.html

Similar work

http://hackaday.com/2012/01/01/hackerspace-light-wall-plays-video-at-30-fps/

Some relevant info

http://waitingforbigo.com/

Code

Driver/development framework

Server running on node.js, control for any games using a browser window, interface with the wall using a C/C++ written node module.

Create online api for running code on the screen

It would be cool if people could browse to a site and enter code that they can run on the screen.

Great fun for teaching people about coding...

This does mean that you create a gateway for someone to run code on the server, and this code could be hostile.

How to keep it secure:

http://nodejs.org/api/vm.html#vm_vm_runinthiscontext_code_filename http://nodejs.org/docs/v0.3.1/api/child_processes.html#child_process.spawn

Software

Snake

A game of snake. This project is almost done. It just requires some more practical website for controlling the snakes (right now they can be controlled using keyboard, which sucks for smart phones). See Snake implementation

Super bomber man

No work done yet

Blocking issues

It is practical to only work on it after better abstracting the framework to be used.

Conways Game of Life

A cool screen saver.

Non member participants

Herman Kopinga