XBMC Community Forum
XBMC on Raspberry Pi - Wonder if this will work out? (Historical Discussion Thread) - Printable Version

+- XBMC Community Forum (http://forum.xbmc.org)
+-- Forum: Help and Support (/forumdisplay.php?fid=33)
+--- Forum: XBMC General Help and Support (/forumdisplay.php?fid=111)
+---- Forum: Raspberry Pi Support (/forumdisplay.php?fid=166)
+---- Thread: XBMC on Raspberry Pi - Wonder if this will work out? (Historical Discussion Thread) (/showthread.php?tid=113824)



- davilla - 2012-01-23 17:21

macf1an Wrote:they say it's likely it could

http://www.hdmi.org/learningcenter/kb.aspx?c=6#42

"They" need to learn basic electronics. This platform requires about 2 Watts of power. Lets ignore peak current draw and just assume 2 Watts for simplicity.

Watts = Voltage * Amps.

2W / 5V = 0.4A or 400mA of current.

400mA > 50mA Smile Not a chance. But notice that it is in the range of being powered via USB which is 500mA @ 5V.

On electronic devices, you MUST meet both voltage and current limits or risk the device blowing up (over voltage) or behaving badly or not at all (under current).


- Bagheera - 2012-01-23 18:01

Besides ... whats the point? If you have a TV near the Raspberry its most likely that you have power too :o


libCEC/CEC - effbiai - 2012-01-23 18:02

@davilla Will the "out of the box xbmc for R-Pi"-release support CEC?

EDIT:
davilla Wrote:Wrong, the platform has to support a) native cec in hardware and provide a cec API that xbmc understand or b) have a USB port that can accept a cec device that libcec supports.

guess not Smile


- effbiai - 2012-01-23 18:05

Bagheera Wrote:Besides ... whats the point? If you have a TV near the Raspberry its most likely that you have power too :o

it would have bin nice to "hide the box behind a tv on the wall". anyway.. it's possible to power it with USB and alot of modern TVs has USB connections.
what people can do is to power up the device via USB and connect it via HDMI behind the TV, which is really neat Wink


- PaulC2K - 2012-01-23 19:00

effbiai Wrote:it would have bin nice to "hide the box behind a tv on the wall". anyway.. it's possible to power it with USB and alot of modern TVs has USB connections.
what people can do is to power up the device via USB and connect it via HDMI behind the TV, which is really neat Wink

I was wondering something similar, however it would surely have to be a powered USB socket, simply being able to accept a USB stick to watch videos and look at photos isnt the same thing, but assuming its powered i guess it could work.
I'd love to power one out of the USB socket in a Sky TV box, pretty sure it wouldnt though.

Also, arent you likely to be requiring a network connection, i wouldnt have thought wifi would meet most peoples demands (no idea tbh) with HD content. You'd almost certainly be connecting more than just a HDMI and USB for power, at least you do if you want a decent range of content on-demand. Music might just cut it with memory cards & usb sticks but not video. USB would stem from the Pi, but it'd still be another wire, but thats nit-picking Big Grin


- darkscout - 2012-01-23 19:50

(Hint, Most TV's have a USB looking "Service Port").

It's how I charged my phone at my mom's over christmas.


- CrashX - 2012-01-23 20:23

@davilla:

Have you had any chance to run some network tests on it ? How fast is it transfering files ? How is the cpu usuage during transfers ?


- Razor_109 - 2012-01-23 21:07

A600 Wrote:Does it support hardware deinterlacing?

Wondering about this aswell... how will it perform Live-TV wise? Any ideas yet?


- davilla - 2012-01-24 03:24

CrashX Wrote:@davilla:

Have you had any chance to run some network tests on it ? How fast is it transfering files ? How is the cpu usuage during transfers ?

No. Useless test. Smile Any modern embedded box can saturate 10/100 Ethernet.


- MilhouseVH - 2012-01-24 07:54

effbiai Wrote:@davilla Will the "out of the box xbmc for R-Pi"-release support CEC?

EDIT:


guess not Smile

The R-Pi GPU certainly supports CEC, but the closed-source Broadcom GPU driver doesn't currently surface the CEC codes to userland in order for the ARM core to gain read/write access. Maybe such support will be added later but it will only come from Broadcom/R-Pi Foundation due to the closed nature of the driver (Broadcom have, apparently, demonstrated CEC working with their GPUs).

If/when the GPU driver supports CEC, then perhaps it can be supported by XBMC.

davilla Wrote:50mA @5V, I don't think that quite cuts it.

According to the hdmi.org link provided previously, 55mA is the minimum provided on the 5V line which is pretty much useless in terms of powering most devices, and since there is no set standard for negotiating or acquiring a higher current (which may or may not be available) it seems highly unlikely that this is a useful avenue for anything practical as the chances of it actually working (ie. enough current available between two random devices) is so low.

As it is, the R-Pi requires 1A@5V to operate, so it won't even be possible to power the board from a single USB port, though it may be possible using two powered USB ports and a Y-cable.