Review: Raspberry Pi No review is ever written in isolation, absent from context. Usually, you can guess the reviewer's bias within a few paragraphs, and compensate accordingly. He hates LCD display quality, she dislikes proprietary software, they yearn for the days of full bandwidth vinyl. You get the idea. Raspberry Pi ARM PC Raspberry Pi …
This post has been deleted by its author
>Feel free to try then.
Thanks for the permission but I'll pass and as you fail to see the point of this board I'll make it as clear as possible. If someone was so inspired as to try then it has succeeded in it's objective of stimulating the pioneering spirit you seem to have long ago given up.
Just because you see obstacles which may or may not be unsurmountable others may wish to have a go and should be encouraged. They may not succeed but they will definitely learn something along the way.
I get it @Chris W you have no clue what you're talking about, do you even know your GPU from your PSU?
Reverse engineering the Pi GPU would not be "pioneering spirit" it would be a utterly useless waste of time since that particular SoC is not available for sale to the public. Actually, since Roku changed their design I don't even know anyone else using it other than the Pi foundation.
There are however other cores widely available on the market that are much more appealing such as the Mali 400, which already has a functioning open-source stack.
This post has been deleted by its author
> Oh dear, you don't even know Monkey Island references?
> You're posting on an IT related site why exactly?
Wrote my first program in 70s, continued throughout the 80s, moved into system admin in the 90s, set up my own IT company in 1998 and I'm now retired.
Why the fuck should I know anything about monkey island and what does it have to do with IT?
"If you need to reverse engineer the GPU you could try asking the linux community. They being doing that sort of thing for years."
Well yes, with some varying degrees of success of course. It's not easy peasy (I worked on reversing the Tseng Labs ET4000 on the well known x86 platform and that was enough for me, can't even imagine the work involved for an ARM-connected 3D core)
The other problem as I said is there's no good argument to make for reversing the Pi's GPU, because this GPU is almost exclusive to the Pi.... The Roku 2 is the only other platform that uses it, but the Roku 2 has so far never even been rooted and is now deprecated, so a graphics driver for that is not something that's really needed.
If the foundation changed their SoC in a future Pi all the many months (years?) of work would be rendered useless.
"Wrote my first program in 70s, continued throughout the 80s, moved into system admin in the 90s, set up my own IT company in 1998 and I'm now retired.
Why the fuck should I know anything about monkey island and what does it have to do with IT?"
You do sound like a sad and bitter person.
""Wrote my first program in 70s, continued throughout the 80s, moved into system admin in the 90s, set up my own IT company in 1998 and I'm now retired.
Why the fuck should I know anything about monkey island and what does it have to do with IT?"
You do sound like a sad and bitter person."
I don't think so, although it might sound like that to you because you are a twat.
> Look up George Mallory
Thanks for educating me about Mr Mallory, apparently he died trying to reach the Everest summit.
But this is related to reverse engineering a GPU how exactly? If you're using Everest as a metaphor, maybe a successful explorer who didn't die would be a better example.
Plus the Everest was and is not going away anytime soon, any exploration you do will be useful for generations to come, while by this time next year this little SoC will be in the scrap heap and forgotten.
>>much of the hardware is undocumented
Tell us how much, say NVidia, is documented.
As to the Raspberrypi dot org itself:
"Broadcom don’t release a full datasheet for the BCM2835, which is the chip at the heart of the Raspberry Pi. We will release a datasheet for the SoC which will cover the hardware exposed on the Raspi board e.g. the GPIOs. We will also release a board schematic later on."
>>much of the hardware is undocumented
>Tell us how much, say NVidia, is documented.
Why NVIDIA? I'd never use NVIDIA for any computer whose hardware I wanted to hack around with.
NVIDIA is evil, they've just dropped Linux support for PC chipsets with their Optimus tech.
The Mali 400 on the other hand is already pretty well documented.
As someone who works for Broadcom (on that particular GPU) and volunteers for the Raspberry Pi foundation, I can categorically say that the GPU you say is only used in the Roku device is also used in at least 5 current production mobile phones, as well as numerous other devices, so I think perhaps you need to revisit your arguments.
I wonder if you are thinking of the particular chip, the BCM2835, that has the GPU in it, which is currently used in the Roku device and the RaspberryPi. That particular chip contains the GPU to which you refer (A videocore4), but it isn't the only chip that does so.
Even Wikipedia has the information which you are missing.
You are correct in one point- it would de pretty much impossible to reverse engineer the GPU.
It runs an ARM11 chip, which (confusingly) uses the ARMv6 instruction set, as opposed to the ARMv7 more commonly found in your garden variety smartphone, so support for the chips isn't that widespread. In theory it'll run any OS you can compile to run on ARM11, but you'll quickly find that that list of OSes quickly degenerates to just Linux, and once you start considering usability that list degenerates even quicker to pretty much just Debian (for now, anyway). It's quite a step from common arm chips and a far cry from your typical x86 beast, so whatever OS you want needs to be one that is supported by a broad community of active and talented developers.
Aside from Linux, RISC OS is the one that's already been mentioned, and you should have no bother running Android on the thing, but after that you're out of luck. There'll be no chance of Windows on Arm because the RPF aren't a windows partner (plus MS aren't selling licenses to end users, just OEMs per device). But really, it begs the question, given the nature of the device; a low cost, educational/hobbyist PC/embedded electronics platform, why would you want to run anything but linux on it?
It's not particularly interesting to BSD really - or at least I've seen no interest from the FreeBSD community. See here:
http://lists.freebsd.org/pipermail/freebsd-hackers/2011-November/036745.html
The Pi is an ARMv6, which isn't that powerful compared to most other (Cortex based) SoC boards. The video out is controlled by a proprietary, closed source system, with no specifications - so there is zero chance of enabling video on a Pi without using the provided binary blob on Linux.
If you want a cheap ARM on BSD that can't do video out, you buy a sheevaplug, or one of the many derivatives. If you want a powerful SoC, you buy a BeagleBoard or a PandaBoard.
"...and once you start considering usability that list degenerates even quicker to pretty much just Debian (for now, anyway)."
I'd say that depends on how you define "usability". If you mean "it's mostly all there out of the box", then I'd largely agree with you; that said, Arch Linux ARM is pretty stable and usable, and many of the programs and services I've got on my Arch/x86 netbook, are available on Arch/ARM on my RasPi (subject to the more limited system resources). Mind you, Arch isn't for the total newbie, and I'm not sure I'd subject the average schoolkid to its quirks, but I like it :-)
No quarrel with the rest of the post, though the question of whether Android will run on the Pi is a bit thorny (I understand it's being pursued, but not much word yet). Like you said: I think I'm happy to stick to Linux on the little fella...
> It runs an ARM11 chip, which (confusingly) uses the ARMv6 instruction set, as opposed to the ARMv7 more commonly found in your garden variety smartphone, so support for the chips isn't that widespread.
You sure about that?
http://en.wikipedia.org/wiki/ARM11#ARM11-based_products
...seems to suggest quite a few phones use ARM11 chips and few seem to use ARMv7 chips?
> ...seems to suggest quite a few phones use ARM11 chips and few seem to use ARMv7 chips?
That list seems to suggest quite a few OLD and retired phones used ARM11 chips, e.g. iPhone 3G is already 4 years old...
Current phones have the more powerful ARMv7 instruction set cores.
The switch between armv6 and armv7 is typically just a gcc flag or two away. And most people don't need to care, as system gcc already is configured with correct flags.
There is not that much speed difference between armv6 and armv7 either in most cases. Neon is sometimes useful, but armv7 doesn't guarantee that either.
Actually, a lot of current generation smart phones use ARMv6 (e.g. ZTE Blade / Orange San Francisco), and practically all Android slates that sell for < ~£120 use ARMv5 processors, as do some NAS boxes in a recent review on this site. ARMv5 is still very popular, cheap, and the performance of some of them is pretty decent (e.g. Marvell Kirkwood). Except for the very latest release of Ubuntu, all Linux distributions support ARMv5 and have no plans for dropping ARMv5 support in the foreseeable future (Fedora, RedSleeve, Debian, etc.). Ubuntu is very much the odd one out for dropping ARMv5 support.
As someone who now wants to try and have a stab at a bit of programming (after dropping out of software design in high school due to never actually paying any attention) the Pi seems perfect - and it's at the right price point for it to essentially be a "no-risk" proposition - here's a computer that can be up and running for a lower overall price than many textbooks, and with a large fanbase already (and plenty of forums to go to for help) it seems it's almost a no-brainer to get one....
The only issue is the reported instability of the hardware, as has been spoken of both often and loudly in other articles on the subject here on El Reg. Having a piece of hardware this cheap sounds perfect, but even if it can't do *much* it needs to do what it can, *well*. If not, I forsee lots of frustration followed by an attempt to expand the functionality by attaching it very quickly and briefly to the heavy end of a large hammer.
I do hope stability can be sorted out and it succeeds though, with a dedicated fanbase I can see people doing things with it that the creators never imagined...
@Esskay
If you want to try out some programming there are free tools for your existing computer. If you are Windows based try DEV-C++ if you fancy trying C or C++. Perl and Python interpreters are just a Google search away and if you use a Mac then the world is your oyster as you have access to a hefty %age of the FOSS tools.
(Note to Linux users - I didn't mention Linux as I assume that if they were using Linux they'd know most of the above).
To be fair to them the software instability is exactly why it's been released in its absolutely bare bones to the world of hobbyists and developers first. The foundation want to target schools and children (that sounds sinister), but by flogging 150,000 of the things to techy types first they get us to work out all the linux-tastic kinks before they unleash the thing on kids.
As the other poster said - you have a pc you're posting this from? Then you have a platform you can program already. Install python, or a C compiler, Java SDK, or whatever runtime you want (these are all available free for Linux, Mac and Windows) , find an IDE you like or even just a text editor, then just go for it.
Pi is an interesting device for it's size and cost, but you don't *need* a new machine to code with.
Indeed you don't, but with raspberry pi the wannabee kernelmode developer gets a *cheap* *low risk* machine to play with. Yes you *could* do equivalent stuff on a PC, but when Bad Things happen (as they sometimes do in kernel mode) on the PC, it may take time+effort to fix. On RPi, reflash the flash and start again.
What a load of nonsense. The wannabee kernel mode developer already has a way to do exactly this, by using a vm on their operating system of choice.
I know lots of BSD kernel developers who run OS X on their laptops, and test all their kernel changes in VMs. Very little needs actual hardware to develop upon.
re "you don't need a new machine to code with" . exactly what I thought.
I'm still getting a raspberry pi, but that is because it is small and cheap, and I want to put in places, like home automation, where you only want and require small and cheap low power devices.
if the GPIO pins can be interfaced well to run relays, PWM power control, etc then I can see the RPi being much better than the arduino I've got. On the RPi model B you get ethernet on board instead of on a "shield" like the arduino.
An arduino + ethernet shield is about the same price as a RPi model B, and only has a fraction of the computing power.
I think most of the hardware instabilities are due to poor power supply. The spec requires a power supply capable of supplying 700mA. Many micro USB chargers only supply 500mA. Also, if you're using a power supply with a USB socket and supplying your own cable, make sure you use a decent cable with thick wires. If you don't have sufficient power you'll get random lockups every now and again.
I'm currently using an iPad charger with a Nokia USB->micro USB cable and that's rock solid. Farnell and RS both sell suitable power supplies.
After issues with a Master Plug USB charger (fine for other devices, but not enough juice for the Pi (pun half-intended)), I splashed out £4 for a Nokia AC-10X micro-USB charger on Amazon. They're slightly more generous with the power they dish out, and the Pi has been quite happy ever since.
The Register 
Biting the hand that feeds IT
Copyright. All rights reserved © 1998–2024
