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Re: [LUG] A slice of Pi gets closer...

 

On 16/01/12 11:53, Gordon Henderson wrote:
> On Mon, 16 Jan 2012, Kai Hendry wrote:
>
>> On 16 January 2012 18:04, tom <tompotts@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>>> No - its not just a toy - its a small compact computer. As such you
>>> can do
>>> just about anything with it.
>>
>> Except browse and use it as a Webcam controller for example.
>>
>>> 256 M Ram was quite common on a lot of usable low end android devices.
>>
>> I think most people will go for the 128M option. Probably by the time
>> Rasberry PI is delivered, the Iphone 5 will have 1G of RAM.
>
> It will be intersting to see what people use the R-Pi for. I will get
> one, more out of curiosuty than anything else, but I do have one
> little project I want to put it to use for (as long as the SDL
> libraries work :)
>
> As for the webcam thing - well, I'm confused, but I suspect people are
> either expecting too much or are using the CPU to offload some of the
> webcams data processing - a USB webcam should require zero CPU other
> than that required to get data off the camera and onto the LAN
> connection. a 720p stream is not that fast compared to Ethernet.
>
> And if you're going to do that, you might as well use one of the USB
> <-> Cat5 extender cables discussed here recently than waste a
> processor board to do nothing more than act as a media convertor.
>
>>> It might not run badly written bloatware but the CPU is around 1000
>>> times
>>> more powerful than the old DEC machine I used to use with 20 other
>>> engineers
>>> and 130 secretaries on 1 meg of ram. And its got a gpu too....
>>
>> My thinkpad has a GPU which fails to render any 3D. :}
>
> More likely it's lacking the drivers or application software to
> utilise the GPU...
>
>> If you want to tackle bloatware, don't run http://linuxmint.com/ In
>> fact think of shunning any GNU and Linux altogether for a BSD flavour.
>> ;)
>
> Remind me again, which C compiler is the default under *BSD?
>
> ;-)
>
> The software tools we use are becoming bloated - an example is the
> 'grep' command - and this applies to both the BSD and GNU versions...
> Once upon a time to grep through files recursively, you'd couple it
> with another tool called find - e.g.
>
>   find . -name \*.c -exec fgrep longVariableName {} /dev/null \;
>
> Now, you simply:
>
>   fgrep -R . longVariableName
>
> The -R flag tells grep to go recursive.
>
> So grep has been bloated by adding in code to recursively scan
> directories - although this is worse IMO as there's no easy way to
> just scan for *.c files, so it's going more work. (GNU grep has
> --include/--exclude, BSD doesn't IIRC)
>
> Worse - fgrep had a new flag added which I always forget: "-l". In the
> olden days grep would only print the filename if it was given 2 files,
> hence adding /dev/null to the find command - it's minor, but it all
> adds up nevertheless...
>
> Another annoyance I have is ssh... Once upon a time we had rsh -
> great, but no encryption and it was easy to mis-configure to be
> insecure. So why whinge about ssh? It's encrypted and you can't turn
> it off by default - a good thing many will say, until you need to use
> it as the back-end for rsync to copy 100's of GB of data from a
> slowish server to a new one, or over a Gb LAN, etc. then the overhead
> of the encryption really slows it down - I've seen ssh burning 50% CPU
> usage on a 3GHz processor when used with rsync. The data rate goes
> down too - struggling to reach 100Mb at times, even though the disk
> drives can sink/source 10x that rate. So now I'm looking at going back
> to rsh for some LAN based servers which need to exchange a lot of data
> via rsync.
>
> And so it goes on with everything - now we need windows with rounded
> corners, anti-aliased, and a bit of transparency to make the rounded
> corners allow the background to show through. That adds 100's of lines
> of code which have to be executed, making things slower - until you
> give it a faster processor.
>
> However, we've more or less reached processor top-speeds for now -
> enter the GPU(s) get the main CPU to offload the prettys to the GPU -
> if it can, but that needs more code to run in both the main processor
> and GPU - complexity goes up to a state where it's almost impossible
> for one person to fully comprehend all the workings of a modern PC.
>
> Gone are the days of knowing an Apple II or BBC Micro in & out -
> knowing what ever peek/poke meant. Is that a good or bad thing? I'm
> not sure. Who knows.
>
> Gordon
>

Ah like on the spectrum poke 23609,255 which IIRC would beep when you
pressed a key on the keyboard 

--
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skype : psutton111


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