

Raspberry Pi - The alpha boards are here - DanWaterworth
http://www.raspberrypi.org/?p=78

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cturner
I get the impression that it's becoming easier to knock together a linux
system on a custom motherboard build around ARM.

I have a project where I'm trying to get USB-to-ethernet to work for
pandaboard. But I'd prefer to have two ethernet adapters on the board.

If it's becoming straightforward to built these platforms, how long until you
can just go to a website, click some checkboxes, and order a set with the
features you want?

Update: another issue. If you're running several of these things, you need
multiple DC adapters plugged into the wall. This seems like waste - it would
be useful to have a single power unit with multiple leads. Does anyone have
ideas about getting such a unit?

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mcpherrinm
I've been looking into embedded ARM systems with ethernet lately.

The Pandaboard & Beagleboard are completely out since my embedded RTOS
application has no USB stack.

The two boards we're dealing with are the TS7800 and the Gumstix Overo series.
For you, the Overo on a Tobi Duo is a reasonable way to get dual ethernet,
though it's only 100mbit. The 7800 has only a single gigabit.

The abundance of embedded ARM devices is really a great thing for small
projects. A small, passively cooled ARM computer can do most tasks that you'd
have needed a 1U rackmount system for only a few years ago.

As well, they're great for learning. Bootstrapping an operating system from
nothing is far, far easier on an ARM system than an Intel/x86 one.

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eterps
Do you have more information or some links about OS development on ARM?

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lgeek
Implementing an operating system isn't that different between the main CPU
architectures. I think mcpherrinm was just saying that you have to do a lot
less work than for x86, for example, in order to get a minimum of
functionality.

Unfortunately I don't know of any guides on implementing a toy OS on ARM. The
operating systems course I've taken was a decent starting point, but it mostly
deals with theory: [0].

There's also a first year ARM architecture course: [1]

Another course I've taken was about ASM programming on ARM, plus programming
some simple hardware[2].

I'm not sure how useful are those materials for someone not taking the
courses, but they might offer a list of things to look up somewhere else.
Wikipedia actually has some good background theory.

Finally, you might look over the ARM port of EDK2[3]. EDK2 is a BSD-licensed
implementation of UEFI[4]. It implements a lot of the functionality of a
regular operating system, with the notable exception of multithreading. I find
the source code of EDK2 to be easier to understand than the source of the
Linux kernel. Probably because it is a lot more lightweight. You can run it on
BealgeBoard, by the way. I'd say it's alpha quality software at the moment, so
you might get some weird bugs.

Disclaimer: I'm a CS student at Manchester University and I work on EDK2.

0: <http://www.cs.manchester.ac.uk/ugt/2010/COMP25111/>

1: <http://www.cs.manchester.ac.uk/ugt/2010/COMP15111/>

2: <http://www.cs.manchester.ac.uk/ugt/2010/COMP22712/>

3:
[http://sourceforge.net/apps/mediawiki/tianocore/index.php?ti...](http://sourceforge.net/apps/mediawiki/tianocore/index.php?title=EDK2)

4:
[http://en.wikipedia.org/wiki/Unified_Extensible_Firmware_Int...](http://en.wikipedia.org/wiki/Unified_Extensible_Firmware_Interface)

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watmough
Fantastic. If I understand correctly, they've switched from the teeny board
(or is that a model A?) to a larger board that will be shrunk to credit card
size in production, with expanded I/O, USB, HDMI, SD, 10BaseT.

Really looking forward to getting my hands on one of these.

~~~
bane
That's interesting...any idea why? I was always under the impression the teeny
USB stick device was the entire device.

~~~
mcpherrinm
The alpha boards are not going to be the same as production. These are
prototypes and are a step towards a finished product.

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zdw
I'd love to see an ARM based router with a decent amount of flash and RAM.
Most of the current ones are MIPS based.

The reason for this is that there are a lot of interesting ARM-specific code
for embedded devices, like LuaJIT and similar.

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dstein
You can use one of these as a router:

[http://www.globalscaletechnologies.com/t-guruplugdetails.asp...](http://www.globalscaletechnologies.com/t-guruplugdetails.aspx)

It has 2 ethernet jacks, wifi, and draws 5W.

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FraaJad
Please, for the love of all that is holy, please stay away from Guru plugs.

I got three (I wanted one, boss ordered three, sigh!) of these to develop on a
"ARM", when Tonido did not have enough in stock.

These sound like a small turbine. It is impossible to work with these switched
on.

The earlier versions were heating up so badly and melting electronics, that
the manufacturer decided to put a crappy fan inside and create a new problem.

~~~
dstein
They have another version that is silent, dreamplug.

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jws
I've been using dreamplugs. They are nicely done. They aren't tiny like a wall
wart, more like a tall paper back book, but I've happily replaced all of my
OpenWRT based systems and won't look back.

Get the JTAG/UART device, it will save your ass when you render the poor thing
unbootable with a kernel replacement. There appears to be a network boot
attempt in the power up, but I haven't seen documentation for it.

One caveat: The wifi range is ok, but not top notch, and when running as an
access point it can only support 8 devices, which isn't much when people show
up with a phone-ipad-laptop bag.

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nitrogen
Is the 8 device limit a hardware or software limitation?

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jws
I think it is in the firmware loaded into the wireless hardware. I browsed
through the driver source and didn't find anything to account for the limit
there.

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nitrogen
The Raspberry Pi site really needs a one-line blurb below the logo explaining
just what it is, or failing that, a prominent "About" link. I shouldn't have
to go through several blog posts, an unhelpful FAQ, etc. just to infer that a
Raspberry Pi is some kind of embedded board that runs Linux, and still have no
idea what CPU it uses or how fast it is.

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malkia
I've got Efika-MX smart top (and there is smart book) and love them. They are
not that expensive - $130 for the smartop, $200 for the smart book.

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gcb
yeah, for the price of a dreamplug you can get a netbook. dreamplug are
useless.

btw, did you get video acceleration on yours?

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malkia
Yes, I do - it's OpenGLES2 using the imx drivers. I think it's PowerVR device.
glmark2-es2 works (though I think there is an artifact with the z-buffer).

They have forums at power-developer.org - very nice bunch of folks.

It's sell Ubuntu 10.10, until they get their drivers up to 11.04, but on the
site there are many other different distress, and even people experimenting
with armhf (hard floating point).

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gcb
openGLES is fine, i was asking more about hardware acceleration for video.

if you play a full HD video, does it skip frames like crazy? is the CPU on
100%?

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malkia
I haven't tried any video on it. Check power-developer.org

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bane
ETA for somebody to hack together their own handheld emulation console using a
Rasberry Pi as the computing core? 6 months.

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drivebyacct2
I can't remember what this is, the "home" page is a list of their recent blog
posts and their FAQ is useless to anyone who doesn't know what Raspberry Pi
is. How do so many people make this mistake?

