[lug] Mailing lists/forums for embedded?

[Michael J. Hammel]

On Wed, 2013-08-14 at 00:19 +0000, stimits at comcast.net wrote:
> For basic device requirements, preferably dual or quad core, 

Take a look at why you might need this.  Dual or quad will have higher
power requirements, and many of the small boards try to avoid that so
stick with single core.  You can get quad core ARMs, but they're pricey.
I'm amazed at what you can do with the Beagleboard and Raspberry Pi with
single cores if you make use of hardware accelerated graphics or, in the
case of the Beagleboard, the DSP.  Even without hardware acceleration
they can do some pretty amazing things.

> with several USB 2 ports (I plan to modify drivers), 

I have a need for 7 USB ports on my project.  Someone in the UK has an
expansion board that connects to the GPIO pins on the Raspberry Pi.  The
Pi itself has two ports but power requirements mean that using those
require an externally powered hub.  I've seen one guy who ripped apart a
bunch of 7 port hubs, connected all the boards and made a 32port hub.
Pretty cool hack.  

That's another thing to look at: makers.  Make Magazine is a good place
to start with that.  And look on Kickstarter for tech projects.  Just a
bunch of places to get ideas, which is motivation to pick something and
get going with your own project.

> and audio capabilities (by this I would prefer 7.1 hidef, but could
> use AC97/5.1, or even stereo, along with the ability to do some FFT on
> it). 

I'm not educated on audio issues.  The Pi and Beagleboard have audio
support but I doubt its 5.1.  My media box will stream video to another
Pi running XBMC with an audio out split to two small JBL speakers.
That's good enough for me.

> A single ethernet port would work, but dual ports I can put in
> bridging mode would be great. 

Ethernet phys and connectors take up a lot of space.  Many small boards
rely on USB wifi or even bluetooth or xbee.

> Ideally I could run RTlinux, but any linux would do (e.g., android).
> Trouble is that I have way too many questions, and am not even sure if
> I know what the right questions are.

RTLinux isn't needed unless you have very tight timing requirements for
your application.  I built a radar system with 8ms timing requirements
that didn't need RTLinux.  High speed timers go down to 4ms on the
PowerPC I was using.

> So...what mailing lists would be the place to go to get hardware
> advice on this?

If it's Linux-based hardware, what's wrong with this list?  :-)

FWIW, both the Beagleboard and Raspberry Pi communities have very active
mailing lists. SparkFun has an IRC channel which I found helpful when
doing my first Eagle drawings.

http://beagleboard.org/Community/Forums
http://www.raspberrypi.org/phpBB3/
-- 
Michael J. Hammel <mjhammel at graphics-muse.org>