[Info-vax] [OT] Raspberry Pi, was: Re: Intel junk...Kernel-memory-leaking Intel processor design flaw forces Linux, Windows redesign

[Paul Sture]

On 2018-01-11, Simon Clubley <clubley at remove_me.eisner.decus.org-Earth.UFP> wrote:
> On 2018-01-11, johnwallace4 at yahoo.co.uk <johnwallace4 at yahoo.co.uk> wrote:
>>
>> The Raspberry Pi exists because one of the founders,
>> Eben Upton, who at the time was teaching at Cambridge 
>> University, got seriously concerned about the lack of
>> understanding shown by his undergraduate intake. This 
>> too is widely documented, e.g. Eben Upton's IET Young 
>> Professionals lecture from 2012 (around 45 minutes):
>> https://www.youtube.com/watch?v=-P46sRDDONI
>>
>
> The Raspberry Pi is ok if you just want to use a supplied version
> of Linux and run applications on top of Linux but it is an absolute
> disaster area if you want to use it at a lower level with bare metal
> programming.
>

See video @ 34:30 "Add-on boards". Eben says that he's a software guy,
and making a dot move around on a screen isn't as cool as it once was;
what kids today find interesting is making a little thing move around on
the floor.

He goes on to argue that the Pi should not be seen as a competitor to
the Arduino but as something which is complementary.

"What good about Arduino? Very low power and very low cost."
"What's bad about Arduino? You need a host PC to run it from"
"What does a Pi give you? It's a very very very cheap host PC"


> Here's a simple example: feel free to show me the freely downloadable
> location for the official datasheets and manuals for the Raspberry Pi's
> USB controller.
>
> They are not available unless you are a customer of the vendor who
> supplied the USB controller for the Raspberry Pi.
>
> This doesn't even cover all the historical problems with getting data
> on the Raspberry Pi's GPU and the last time I checked some of that
> information was still closed to the public.
>
> For example, the initial boot sequence on the Raspberry Pi uses a couple
> of closed source files which you have to place on the SD card. This is
> because the initial boot sequence is controlled by the GPU and not the
> ARM MCU.
>
> The ARM MCU is actually held in reset for the first part of the boot
> sequence until after the GPU has finished initialising the hardware
> and the last time I checked, this boot code was totally opaque; there
> was no public documentation available which would allow you to write
> your own initial boot code.
>
> So much for the Raspberry Pi being an excellent hobbyist or learning
> platform.

I think you are overestimating what it's supposed to be.  Like Eben
stated, there are other bits of kit for the hardware enthusiasts.

Have you looked at any of the pure beginners tutorials that are
available out of the box with a Pi?  The first one I looked at
really had me thinking "Wow, I would have loved this stuff at the
age of 7 or 8".  It was something like a simple text triangle but
it was a pretty good introduction to mathematical progressions.

-- 
Macs. They used to smile at you.