Re: Advice sought on implementing a new homebrew IR receiver

[<li...@ba...>]

Hi!

Martyn Welch "ma...@we..." wrote:
[...]
> A while back I integrated a simple "homebrew" IR receiver and
> transmitter on a MythTV box that both my partner and I have become
> rather attached to. One thing I have noticed is that, I assume due to
> the method used to control the timing for the pulses, video playback
> stutters a little when the remote is used. I doesn't happen when I use a
> wireless keyboard...

LIRC does not use many cycles when receiving. Only on transmit it will use  
the CPU a lot.
If the video stutters during receive, your system is on its limits  
already.

[...]
> This raises a few questions:
>
> 1) Am I re-implementing something that's already done and I've just missed?

Probably. Just try not to reinvent a protocol on the serial port.
Try using something existing like e.g. UIRT or Irlink.

> 2) Is this a reasonable approach or can you suggest a better one?
> 3) Is 1us accuracy a requirement or is some of this accuracy thrown away
> during signal detection (i.e. could I get away with being less accurate?)

100us should be enough. Most commercial receivers use 50us. The Streamzap  
receiver even works with 256us.

Christoph