Raspberry Pi - $35 Linux computer

  • Thread starter Thread starter daz
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My first thought would be that Gentoo would be the optimum system for this - everything compiled in place with perfectly tweaked compile options. Then it occurred to me just how long it would take to build Gentoo on one of these machines - I was doing some rough estimates under QEMU with ARM1176 and it wasn't exactly quick. I'm not so sure just how much of that is QEMU though.

As the Raspberry Pi hardware is common then there should not be any issues with starting from a Stage 3 Gentoo image, as it will already be optimised for your hardware. The problem comes with getting to the point where a State 3 image is availale :(
 
My first thought would be that Gentoo would be the optimum system for this - everything compiled in place with perfectly tweaked compile options. Then it occurred to me just how long it would take to build Gentoo on one of these machines - I was doing some rough estimates under QEMU with ARM1176 and it wasn't exactly quick. I'm not so sure just how much of that is QEMU though.

The other thing we still need to work out is what the GPU can actually do as I've yet to see tests using the binary blob from Broadcom yet...

Yep! It is the first thing I will try to put on
 
It can at least play Quake 3...
and play 1080p video...
I saw these videos, but we're still not sure what state the blob is in. It's like saying a GTX580 can achieve 1.6Tflops and encode video super-fast, but unless the drivers are up to the task then it doesn't really matter. There's also the issue of actually getting software to use the blob; I think the 1080p30 decoding is only for a specific set of video profiles (H.264 BDDVD is the main one, at a guess).

Also bear in mind that Quake 3 came out 13 years ago and was designed to run on things like the Voodoo 2. You could probably emulate it in pure software on a modern machine (although not RPi).

As the Raspberry Pi hardware is common then there should not be any issues with starting from a Stage 3 Gentoo image, as it will already be optimised for your hardware. The problem comes with getting to the point where a State 3 image is availale :(
There's a Stage 3 image for Gentoo for ARMv6, but I don't know if it has hardware floating-point or not. (That's the big difference from armel on Debian, and hence why they're looking at building the special version). I'll be looking at doing it fully today or tomorrow in QEMU, then if it matches enough I'll just dd it to an SD card and see what happens when my RPi actually arrives...
 
Xbox 1 couldnt even manage 720p playback so not at all similar

That's what it says in their FAQ:

How powerful is it?

The GPU provides Open GL ES 2.0, hardware-accelerated OpenVG, and 1080p30 H.264 high-profile decode.

The GPU is capable of 1Gpixel/s, 1.5Gtexel/s or 24 GFLOPs of general purpose compute and features a bunch of texture filtering and DMA infrastructure.

That is, graphics capabilities are roughly equivalent to Xbox 1 level of performance. Overall real world performance is something like a 300MHz Pentium 2, only with much, much swankier graphics.
 
That's what it says in their FAQ:
The two of you are comparing video decoding versus rendering (e.g. gaming) performance here, so you're both kinda right.

The Broadcom chip has special hardware for video decoding, letting it do the 1080p stuff, whilst having ~Xbox 1 rendering capabilities. I think the Xbox had special MPEG decoding for DVD playback as well (which won't be any good for 720p content). Edit: Nope, apparently the P3 chip did all the decoding.
 
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Yeah, it's looking less and less likely this will turn out to be a good media center.

Really? XBMC is about as good as media centers get. Openelec is already supported and there are at least 2 other ports of XBMC running on alpha hardware at very good speeds already.

What do you want.. Windows media center? :D
 
Indeed its looking like the most perfect media centre I could possibly imagine.

I can't wait to get openelec on it and use them for media extenders round the house... I can even power them of the tv's usb. Perfect!
 
Indeed its looking like the most perfect media centre I could possibly imagine.

I can't wait to get openelec on it and use them for media extenders round the house... I can even power them of the tv's usb. Perfect!

Keep in mind at the moment its only going to hardware accelerate x264, anything else will run through the CPU unless either Broadcom make other formats available or someone does something clever with OpenGL. Also the USB Power standard is 500ma not the 750ma Raspberry Pi recommend so don't take it for granted that it will power from a standard USB socket.
 
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For all those looking for a case

http://www.ebay.co.uk/itm/Genuine-R...ltDomain_3&hash=item460182fb05#ht_2457wt_1396

:p

Q: I represent a Middle Eastern government that wishes to integrate an RPi into all of its RPGs. Do you offer a mil spec variant? My client has had success with mil spec casings based on http://*******.com/85u3yh2 technology.
A: Soz mate. Dead link. Try harder next time. 2/10 I'll put in in the listing, if it's decent ;-)
Q: I tried to post this on facebook but it says it is spammy and wont let me. Does it contain meat?
A: I contacted FB over this issue, still waiting a reply :-(
Does it contain meat?
pmsl :-)
Q: Nice design. Does it have a spare USB port hole, or do I have to cut it out myself? Also, do they come in green?
A: Cheers, no, yes, no ;-)
Q: is there a 19" rackmount version please?
A: No, I recycled the box the flat screen telly came in.
Q: is it water proof down to 30 metres?
A: Are you? I haven't run full H&S on it. Bought as seen :-)
 
Keep in mind at the moment its only going to hardware accelerate x264, anything else will run through the CPU unless either Broadcom make other formats available or someone does something clever with OpenGL. Also the USB Power standard is 500ma not the 750ma Raspberry Pi recommend so don't take it for granted that it will power from a standard USB socket.


Not true, it also acelerates MPEG4. This means most .avi and .mkv that are commonly used will be hardware accelerated.

I'm told most recent phone changers with a microusb adaptor (standard now I believe) with a ac adaptor should power it fine.
 
Not true, it also acelerates MPEG4. This means most .avi and .mkv that are commonly used will be hardware accelerated.

I'm told most recent phone changers with a microusb adaptor (standard now I believe) with a ac adaptor should power it fine.

10 internet points to you! I had missed the MPEG4 decoding, that makes things a little more interesting. I belive you are told most phone chargers will power it fine because most phone chargers are 750ma these days, it still doesnt imply it can be powered off of a standard USB socket on the back of a TV, it might work but I would have thought the 750ma requirement was set for a reason.
 
10 internet points to you! I had missed the MPEG4 decoding, that makes things a little more interesting. I belive you are told most phone chargers will power it fine because most phone chargers are 750ma these days, it still doesnt imply it can be powered off of a standard USB socket on the back of a TV, it might work but I would have thought the 750ma requirement was set for a reason.

Isn't the non-powered output spec for USB 2.0 a maximum of 500ma draw? So it *might* work but once more current is drawn than 500ma it *might* stop working? 700ma is the model B requirements and model A is 300ma. Hell they say 4 x AA batteries should do the trick!
 
Isn't the non-powered output spec for USB 2.0 a maximum of 500ma draw? So it *might* work but once more current is drawn than 500ma it *might* stop working? 700ma is the model B requirements and model A is 300ma. Hell they say 4 x AA batteries should do the trick!

Yeah I'm pretty certain it would be fine with no powered USB devices hanging off it but once you add a usb wireless adapter things might get a bit iffy, definately worth a try though the worst that could happen is it powers off.
 
Yes the power requirement for model B's (all current Pi's) is technically out of spec for running off a regular USB socket. I would imagine it will be a "suck it and see" approach to see what will work and what will not. A microusb -> wall socket plug is probably safest if people are trying to get stuff now to work with Pi's that have been ordered.

EDIT- We may have a wait a little longer for our deliveries. Check this out..

http://www.raspberrypi.org/archives/781
 
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