[[http://www.righto.com/2009/08/multi-protocol-infrared-remote-library.html|lib]]


** Flat square one big **

IR bit format 

- (13 or 12 pulses)
- pulse length wide or short (like morse: mark or space )

given 1=long and 0=short it can be decoded as bit stream

format of bit stream
<code>
KEY   ABCDEF GHIJKLMNOPQRSTUVWXYZ 
1     001000 00000000000000000010 
      000010
</code>

A-F are prefix..where

A-B are always 0

CD=10 or EF =10 alternating on each single key press

if long key press the CDEF signature is the same for every repeat

This helps detect single clicks vs long holding...