Date : Tue, 27 Dec 2011 04:12:52 +0100
From : rick@... (Rick Murray)
Subject: About ARM PC
On 23/12/2011 17:40, Daniel Alejandro Benavides D. wrote:
> http://www.bbc.co.uk/news/technology-16316439
ROTFLMAO!
Quote [students *are* the processor]:
--8<--------
It was a noisy, confusing and funny simulation and, once everyone knew
what they were doing, managed to reach a maximum clock speed of about
one instruction per minute.
--8<--------
> I want a Raspberry and Acorn BBC Micro software ports on it.
> Questions: what are the clock speeds of the ?-controller?
> Does this need an Embedded OS?
It will run an OS from an SD card. By default, some version of Linux
(though not Ubuntu, it's an older ARM core (ARM11) and Ubuntu have
dropped support for it (...the elitist b**tards, it's not like it's an
ARM6!)).
Obviously, loading up from SD card means it'll be a doddle to install
RISC OS, or any of a number of ported platforms. Maybe even a hobby toy
for rolling your own mini-OS?
As for the technical question, did you not try Wikipedia?
Quote:
--8<--------
The design includes an ARM1176JZF-S 700 MHz processor, 128 or 256
megabytes (MiB) of memory, intended to run Linux or RISC OS.[2][3] The
design does not include a built-in hard disk or solid-state drive,
instead relying on an SD card for long-term storage.
--8<--------
[yay, a mention for RISC OS!]
The chip itself is a Broadcom BCM2835. Details at:
http://www.broadcom.com/products/BCM2835
but, look, still no mention of a datasheet, nor one on Google, which
makes working with the hardware an exercise in fiddling with other OS
sources, plus something of a joke making GPIO available with no docs on
what it's all about or how to do it.
If I sound a little annoyed about the datasheet... my PVR, Neuros OSD.
Been there, seen it, done it. Had to rip the three-part databook from a
Chinese server because TI simply WERE NOT going to budge and release the
datasheet. Neuros themselves said something like "you catch more honey
with milk, not vinegar" meaning to be polite and play it softly softly.
Well, they tried, they were ignored. There's still no public datasheet
for the chip. Furthermore, if you read my blog you'll see that TI's
official response to me was (quote):
--8<--------
Thank you for contacting the European Customer Support Center. In
compliance with U.S Export Laws and Regulations, Texas Instruments is
required to know to whom they are providing information or services
In your case we have no information about you or about your company as
you are a private customer and our services are addressed just for
Companies and universities there for I am please to inform you that we
are unable to process you inquiry.
Wish you good luck.
--8<--------
So, not only are TI unwilling to release datasheets, nor is European TI
unwilling to talk to a European person without the approval of the
friggin' Americans (US Export Laws? Dumbass!), but they also appear to
be unwilling to employ somebody who speaks reasonable English. The "I am
please to inform you" can come across extremely badly. The guy is
*SORRY* to inform me, not PLEASE(d).
I think this, and the reliance upon closed-source binaries for the video
encode, are what made the OSD project flounder. Who wants to play with
an open source video recorder when that pretty much amounts to "build
the OS and application code", with the chip itself being a black box and
the DSP libraries likewise. There's so much cool stuff that *could* have
been done...
Oh, and there is, to my mind, *nothing* in the datasheet that would
imply it deserves to be NDA, except for the thoughts of paranoid
pencil-pushers. It's your run of the mill "this does that, these
registers are this, and memory organisation is that". Whoo.
Or maybe TI were deadly afraid we'd work out that the chip is only
capable of handling D1 video (i.e. full frame PAL) when it isn't
actually doing something else like, you know, running an OS. Too late,
everybody already figured that out. But why does the hardware rescaler
scale to 720x288 to then push it to the selected 640x480? *SURELY* the
device can handle more than 288 lines? There's nothing in the datasheet
that says this is necessary. But, then, it is running Linux and http
servers and telnet servers and a load of other crap, so maybe there's
just not enough oomph to go around?
<okay, rant off, you get the idea>
> Does everyone want one?
Model B please. Run some server software on it, hook it up to my
Livebox, leave it running...
No, I don't plan to use RISC OS. Sorry, but I'm way beyond the days of
composite video, and nothing here understands HDMI. It's a shame there's
no VGA output, but I guess the chip can't do analogue video like that.
Or maybe it can? How are we to know...
Best wishes,
Rick.
--
Rick Murray, eeePC901 & ADSL WiFI'd into it, all ETLAs!
BBC B: DNFS, 2 x 5.25" floppies, EPROM prog, Acorn TTX
E01S FileStore, A3000/A5000/RiscPC/various PCs/blahblah...