[Coma] If all you had was an LED ...

Cullen Jennings <fluffy@iii.ca> Fri, 08 June 2012 00:38 UTC

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From: Cullen Jennings <fluffy@iii.ca>
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Date: Thu, 07 Jun 2012 11:40:12 -0700
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Subject: [Coma] If all you had was an LED ...
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Imagine an sensor devices that is very cheap and connects to the network. Lets say the only UI the device has a single LED, or perhaps a red and green LED. 

How would you use these 1 or two LEDs to help manage the device? 

Lots of existing stuff blinks them in various ways to indicate different states of the network (no carrier, connected but no IP, etc). Would it make sense to have some standardized recommendation about this? 

It would be possible to send a small message as a burst of rapidly changing light patterns that was detectable by the video camera on a smart phone. Would it make sense to use this for something like POST codes on PCs? 

What are the various states that an operator would want to be able to see? I'm assuming this is mostly states that are important when one can't get networked base management. 

Thoughts? Pointers to what existing systems do ?

Thanks, Cullen