Oolite Bulletins

The Raspberry Pi was launched today with an announcement on their website at 6am GMT this morning. http://www.raspberrypi.org/

Wasn't that what the last three posts of the day were discussing?

Greyth wrote:

Years ago a byte (bite) was the maximum number of bits that could be processed in any one operation at any point in a computer. On most systems that was 8. Now a byte is considered to be 8 bits - not more and not less. Similarly the term mainframe was the frame of memory in which a computer kept track of all other frames. Now it just means 'large box'.

Hmm. Not quite right.

One binary digit became called a "bit" for ease; it is a contraction of 'binary digit'.

A byte - never spelled bite - was the number of bits required to represent a character and was often 6. Convention settled on 8 bits for representing a character and it is now so well established I don't suppose the 8 bit definition will ever change. For example, Unicode requires many more than 8 bits and UTF-16 is described as "requiring 4 bytes to represent one character".

(One hex digit (0 to F) requires four bits, being half a byte this became called a nybble for no reason other than wordplay.)

The number of bits that are processed in one operation is called a word. Very early microprocessors had a 4 bit word. Mainframes had many different word lengths including 6 and 9 bit; I worked on a 24 bit mainframe. A 64 bit processor has a 64 bit word length. You can have processors where the data word length is greater (typically double) the operation word length meaning twice as many bits of data can be loaded into the Arithmetic Logic Unit in the CPU in one processor clock tick, thereby improving performance, without the overhead of unnecessarily long operation commands wasting storage space.

The term 'mainframe' was the sodding great metal arrangement of shelving and cabinets that held all the gubbins that made up the computer. Whoever told you it refers to a memory frame was winding you up.

Tweets from Raspberry_Pi are suggesting that all the initial batch have been allocated and registrations of interest for the next batch, when ever that is going to be, on the 2 selling sites are currently running at 300 per second.

Good luck to them
Ironfist

Wow. That's impressive.

Could it be the best selling computer of the 21st century?

It's about time something like the Pi happened, i think. A computer that can be wired through the telly is something that vanished with the Amiga and Atari ST, and that's sad. Now, with the advent of all the IBM compatibles and Apples that need a dedicated "monitor" to work, everyone who wants to use a computer has to buy a separate screen for the computer. OK, it's not as bad as it was with HDMI being a computer and telly crossover cable, but it still made computer more expensive.

Maybe that's why the "young computing ability" level dropped. Kids and yoofs can't afford to become computer buffs any more. Parent's can't afford to buy the kit for the kids any more.

I know for a fact that if my lads can wire up a proper computer to their tellies then they'll think it's awesome. Especially without a big, bulky base unit taking up floor or desk space.

I look forward to Pis being everywhere soon. Schools should snap them up and if they don't then OFSTED should lock their staff up in a big room and throw raspberries at them.

I read that it runs a RISC OS as well as a Fedora I've never actually used ROS... anyone been there and done that? What did you think?

Greyth wrote:

I read that it runs a RISC OS as well as a Fedora I've never actually used ROS... anyone been there and done that? What did you think?

I used RISC OS when it was still named "Arthur" (version 0.2 in EPROM, later also RISC OS 1.2 until the mid-nineties).

RISC OS was great and innovative in 1987, it was the first OS to use on-screen anti-aliased fonts IIRC. I loved how you can assign memory to and from running programs by sliders. The build-in BBC BASIC V is the best BASIC version I have ever seen: clean, powerful and excellent integration of assembly language. And it had the best version of Elite until Oolite.

I've never been more in love with a computer than with my Archimedes. (It was not my first love tho - that was a 1979 Sharp MZ-80K, and there is nothing like first love.) I'd love to try present-day RISC OS on a Raspberry Pi, just for old-time's sake.

However, RISC OS uses co-operative multitasking, this means that a program which is not (correctly) written to multitask will hijack the processor until it has finished. In the 21st century, that is a show-stopper to me.

Gimbal Locke wrote:

However, RISC OS uses co-operative multitasking, this means that a program which is not (correctly) written to multitask will hijack the processor until it has finished. In the 21st century, that is a show-stopper to me.

Remember the target audience for the Pi though - it's primary purpose is to facilitate education and hopefully breed better programmers. If the kids/students/teachers using it have to program it PROPERLY for the software to work then that will hopefully result in more efficient programming from those who come through those classes.

Thanks for the info chaps. I wouldn't have the first clue about writing code for multi tasking... but then I'm only really interested in one task... I might just get away with that!

I still run my RiscPC. Using the last of the proper releases of the OS.
I could go on for hours about it ...

Here's some food for thought.

It may well be time to dust off a project I was working on, as the one thing letting it down was a decent development environment. Yes, you could use the build in BBCBasic VI (or even the BBCBasic64 - a 64 bit ready OS + programming language from around 1992) but you would need the 500+ page PRM's to do it.

At the time I used to say you can put an 8 YO in front of RiscOS and they would be producing constructive work in around 30 minutes, it's that intuitive.

Dig around to find out what happened to AcornReplay. Still blows the socks off MPeg.

The programs are usually fit in the processor cache ...

I read the article, although I can't remember much about it! but they were doing years ago what we are now doing? I'm not entirely surprised. Some years ago I became convinced that the speed in g/m hz of a system was not the only measure.

I worked at a vehicle pilot plant as a helpdesk operative for some months. I chanced upon a particular 486-66 PC that outperformed all others (that I attended) by a factor of 2. It did everything in 1/2 the time of any other machine of the same spec. So I suspect that only 1 in every few thousand isn't knobbled in some way? I the same job I also worked on a 386 PC belonging to an American chap posted there. It was faster than any machine in the plant.

Buggeration...

http://www.theregister.co.uk/2012/03/08 ... etworking/

DaddyHoggy wrote:

Buggeration...

http://www.theregister.co.uk/2012/03/08 ... etworking/

As they comments say, "Raspberry Jammed"


<snigger>

Typical. Isn't this the kind of thing that buggered up British engineering in the first place? The details?

However, that said, it's not a major bungle. I just hope for RP's sake that the parts can be sourced. If not then it could spell the end for Pi...