Ledslie

From Technologia Incognita
Revision as of 00:34, 11 November 2017 by Chotee (talk | contribs)
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Projects
Participants Chotee, Thijs
Skills electronics, microcontrollers, linux, mqtt, webservices
Status Active
Niche Electronics
Purpose Infrastructure

Interface to display information

  • It is a Grayscale display of 144x26 pixels that displays information.
  • It lives at http://ledslie.ti and is accessible at the space via a website and mqtt.


Content ideas (in no specific order)

  • Spacealert with message.
  • IRC integration via shardik: .display [message]
  • Indicio audio: What are we listening to?
  • Wifi SSIDs being broadcast.
  • Next and last tram / metro / nightbuses
  • Incoming rain alerts
  • Clocks
  • API/Interface for countdowns.
    • Next TI events
    • TI ALVs
    • Next interesting rocket launch (SpaceX, Soyuz, etc...)
    • Space dates / launches
    • ISS flyovers
    • Zonsopkomst en -ondergang tijden
    • Maan standen. volle maan, nieuwe, etc.
    • http://www.apiblog.nl/
  • External content

How it works

Wifi --RF> Getchip --USB2> Teensy --[data,clock,latch]> Led-pannel

The led-panel takes 20V DC as input. At full output it's pulling about 4A, or about 80W. There's a small switcher-board that supplies the 5v the the getchip and Teensy from those 20V.

The Teensy drive code is here: https://github.com/techinc/ledmatrix/tree/master/ledmatrix144x24

The Ledslie code can be found here: https://github.com/techinc/ledslie

Possible Hardware expansions

  • Add another panel by adding a USB2 hub, and modding another of the led panels with the teensy taking over the driving logic.

FAQ

  • Q: What's that noise? A: The panel is being driven at rates way beyond the original design and we're well in the audible frequencies with the refresh-rates and some components are merrily humming along.
  • Q: Why are some points brighter then others? A: Turns out that LEDs do wear. In their previous life some LEDs were on for years, while others were always off. There's plans to compensate for this in software.