[mythtv-users] How does backend/frontend work with Directv?

[Bruce Markey]

Curtis Stanford wrote:
> I haven't actually set up a MythTV system yet and am not quite clear 
> what the separation is between the backend and frontend. I understand 
> the backend encodes all the video and the frontend decodes and displays 
> it. Has anyone done this separation using Directv or an external 
> receiver? Can someone verify my idea of how this works?

Correct. An easier way to think of it is you have a backend
where ever there is a capture card and can have a frontend
where ever you have a screen.

> - Put satellite receiver in the basement.

Yes.

> - Hook up to backend box capture card.

Right, and setup an IR blaster to change channels.

> - Frontend is next to TV and hooked to backend with ethernet.

Perfect.

> - Remote control on frontend.

Exactly. Therefore, you do NOT want to us a remote that comes
bundled with the capture card where the IR receiver plugs
into the card (because the capture card is in the basement =).

> OK, so when you want to watch TV, the backend changes to the right 
> channel, starts up the ring buffer and fires encoded video to the 
> frontend which then decodes and displays it?

Yup.

> When you fire a remote command at the frontend, does it fire the command 
> to the backend (if necessary, i.e. changing channels)? How does that work?

The IR commands through lirc and keyboard keystrokes go to
the frontend.

There is a control socket and a file transfer socket. There
are a lot of things the frontend(s) and backend(s) need to
negotiate. If the user hits a key in the frontend's UI, the
backend needs to be told to encode the new channel. This is
true for even a standalone machine where one frontend and one
backend are on the same box.

You will also need an IR blaster (IR emitter) for your backend
machine so that lirc on the backend can send change channel
commands to the Directv box.

--  bjm