[Arm-netbook] EOMA-68 passthrough implementation

[Ryan Mullen]

Hi,

On Mon, Jul 9, 2012 at 1:06 PM, lkcl luke <luke.leighton at gmail.com> wrote:
>  that would be absolutely brilliant.  if you use kicad then i would
> also potentially be able to help, as i'm sure would a few others.

I would be using kicad, so that is good. I have more experience with
PADS than with kicad, but I've done one small project with kicad and
it went well.

> also then you could use the libraries i've already done at
> git.rhombus-tech.net.  if you like, email phil at hands.com directly and
> ask him if you could be added to that repository ok, with an
> explanation as to why you need access to the eoma.git repository.  to
> be absolutely clear and unambiguous: the url is:
>
>    url = git+ssh://git@git.rhombus-tech.net/eoma.git

I'll follow up with phil when I'm ready to begin and after I've
familiarized myself with your git repo. Thank you for the info.

>  would anybody like to help finding the required mid-mount HDMI and
> USB-OTG sockets?  ryan, are you considering doing an audio IC of some
> description on the pass-through card, or just leaving that for now?
> (can always do a revision 2.0).

I was planning just to use standard connectors for the signals that
are clearly ethernet, or SATA, etc. For all the GPIO/I2C pins I'd
probably use 0.100"-center plated holes and let the user solder
something.

If there were an IC that could pull the audio out of the HDMI signal
and put it on a headphone jack, I might be interested in using it.
However, I don't plan on getting too fancy, and if it bloats the cost
much, I would hesitate.

I'll need to figure out whether the ethernet connector requires
integrated magnetics - I'll figure all that eventually.

>  btw there is some innnsaaane costly requirement for HDMI's HDCP - you
> might like to consider instead just having a DVI-to-RGB/TTL converter,
> like the TFP401a... oh, that's exactly the IC i put on the diagram
> anyway ha ha :)

I don't know the details of HDCP or its requirements, but if that IC
is sufficient, then I don't see why I should look elsewhere.

Anyway, I'm not a corporate entity and I want to say up front that I'm
interested in this project for purely hobbyist reasons. Therefore, if
you have deadlines, customer demos, conventions, or support worries,
then please do not rely on me to deliver anything at all - the usual
disclaimers apply.

Thanks for the feedback,
Ryan