RPi use cases explained

Here is my take on this odd situation.  There are several needs and types of stakeholders in the Pi ecosystem:

• Conceptual need in EE.  Eben Upton has many times related the problems he experienced while doing student recruitment  at university, where each year's intake candidates were seemingly  less technically experienced than the last.  I can well believe that, because we saw exactly that same problem in my own engineering department, to the point where we had to provide catch-up courses to bring part of the student intake up to the level where they could  understand basic 1st-year EE lectures.  Making very cheap hardware available that encourages experimentation by inquisitive youngsters does seem to address part of the problem squarely by fostering interest and offering direct experience with hardware.  However, it doesn't address the gap in mathematics and foundational science skills.

• Improving IT education.  The UK has a specific problem in school-level IT education, in that over time it became nothing more than vocational training in office skills.  Clearly there is much room for improvement there, but this is almost entirely unrelated to the skills shortage observed in EE recruitment.  CompSci departments might benefit a little if programming were taught in schools, but not a lot because lack of programming skills is not the bottleneck,  Stronger maths skills would be vastly more useful than programming knowledge, and would help EE as much as every other branch of engineering and the physical sciences.  Also, programming is almost always vocational training with just a smidgeon of CompSci education acquired by osmosis on the side, and very rapidly becomes dated.  To compound matters further, a high-level language with a lot of abstraction would tend to be chosen for programming education, which means that pupils would tend to learn little about computer fundamentals unless they have an awesome teacher who explains the foundations along with the programming.

• Cheap media centre.  Don't laugh, this is a major stakeholder group for Pi.  What's more, RPF have always known this, because they have promoted the very strong media capability of the Broadcom SoC countless times in their blog.  They even went as far as to sell licensed codecs which are about as distant from educational as anything could be.  This area may well be getting the most development effort as well, which is reasonable since it plays to the Pi's biggest strength and makes a very large group of Pi users happy.

• Platform for expansions.  It always did seem odd that the Foundation so often stressed the difficulty of reaching their $25/$35 price point, and yet created a board bearing proprietary MIPI DSI and CSI-2 connectors which raised the board cost and complicated PCB routing.  Even more odd is that these MIPI interfaces would not contribute significantly to the board's educational capabilities since USB cameras and displays with open interfaces were readily available at good prices.  The subsequent high investment by RPF in developing camera and display modules suggests that this was a planned business strategy from the start, and it explains why the extra connector cost was considered justified.  One possible view is that there is business advantage in creating a platform for which expansion modules could be produced using a proprietary interface spec that narrows the competition.  Whether or not that was the thinking, it is the current actuality since RPF has invested time and money in expansions and delivered product.

• Enthusiasts/makers hacking platform.  Quite distinct from the needs of EE and UK IT education, a  large group of stakeholders is the worldwide and ever-growing community of makers and related enthusiasts, which may or may not be technical.  This group is heavily interested in creative projects which typically underpin some other area of interest that isn't itself computing.  The Foundation has from the start shown some interest in supporting this group, as evidenced by the board's P1 interfacing header and the near-miraculous provision of SoC peripheral interfacing information from a SoC manufacturer that has shown very little interest in supplying open documentation.  The enthusiast/maker community is strongly aligned with the open source software and open hardware communities since closed/proprietary devices impede rather than support building things.  Unfortunately RPF has been lukewarm in this area as the board is not open hardware, the SoC has very little open documentation, and not all of the software is open source either.  Undoubtedly most of the blame for this lies with Broadcom, but RPF spokespersons have defended the restriction of information themselves as well.

• Commercial for-profit product.  This stakeholder group is small but obvious.  RPF is a registered non-profit, but Premier Farnell and RS are not, and so the Pi has to justify its place on warehouse shelves.  The typically high profits on accessories probably make this quite easy though.

It's pretty clear from the above that the Pi ecosystem has multiple interested parties and drivers, and proceeds along many roads simultaneously with varying degrees of support from the Foundation.

In other words, the Raspberry Pi's concept, rationale, targets and user base are not correlated.

Getting a single view from anyone (especially RPF) is no more productive than all those blind men feeling different parts of the elephant.  To say that it was designed for IT education is completely wrong if intended literally --- Pi would not have been designed as it was nor targetted so strongly at non-educational stakeholders if that had been the primary intention.  This makes the question of "Why is there still no educational release?" a simple one to answer:  IT education was only one driving force, and clearly not a major one.

The only certain position is from objective engineering:  it's an ARM board with specific pros and cons, and it's those pros and cons that determine its effectiveness or otherwise for any given application.  I guess that's more boring than hype-laden official positioning statements by people with vested interests, but in contrast to them, it's accurate.

Morgaine.

Morgaine Dinova wrote:

 

• The subsequent high investment by RPF in developing camera and display modules suggests that this was a planned business strategy from the start, and it explains why the extra connector cost was considered justified.  One possible view is that there is business advantage in creating a platform for which expansion modules could be produced using a proprietary interface spec that narrows the competition. 

Actually the proprietary nature of the interface doesn't seem to be much of a problem. The actual camera sensors with the same interface and physical plug appear to be reasonable easily available off ebay and such like as spares for phones.

The roadblock is the bits that are buried inside the GPU.

I'd have to say that I originally thought the camera was a daft idea, but it's cheap enough that I bought one anyway.  If JamesH manages to sort out a couple of software niggles, I can see it having a reasonable future as a very cheap megapixel security camera amongst other things.

I see someone has already produced an aluminium case with a mount for the camera and externally a mount for additional standard lenses.

I think that's where the maker community shines.. by taking these cheap component parts and combining them into all sorts of interesting ideas.

Just leave her to it, coder27, is my advice.  Like watching a train wreck in slow motion, it's mesmerizing for all the wrong reasons, and a total waste of your time.

I'll be interested again when a new Pi board appears just in case it turns out to be good, although they'll undoubtedly stay with Broadcom so it's unlikely to be open hardware.  Until then, I think everyone knows what to expect from that quarter, and calm reasoned discussion that engages with questions isn't top of the list.

and calm reasoned discussion that engages with questions isn't top of the list.

It is interesting that they have given Gordon Hollingworth the new task of

answering questions:

http://www.raspberrypi.org/archives/4307

Maybe something will come from that.

Or maybe E-14 can be used for productive discussions regarding education.

Clive's videos are based on the GCSE curriculum here:

http://www.ocr.org.uk/Images/72936-specification.pdf

which is essential to understand when discussing the videos.

For example, section 2.1.1 "Fundamentals of Computer Systems"

discusses input, output, processing, and storage, but makes no

mention of software or computer instructions that are followed like

a recipe.  And Clive's blender video followed this closely.

One point I found interesting was the discussion on clock frequency,

based on section 2.1.2.  It seemed to me that he confused the notion

of clock frequency measured in Hertz, or cycles/second, with the

fetch-decode-execute cycle.  Two confusingly similar uses of the

word "cycle". 

User Dio made a comment related to this, and Clive responded:

... I don’t see any “glaring errors” myself, just different ways of talking about a topic to a specific audience. (We call this “teaching” )

...

I’m aware of my use of the word “instruction” here but in this context I’m happy with it as the fetch-execute cycle, and instructions taking more than one cycle, are dealt with in a previous topic.  ...

This is a very interesting discussion.

The points made seem to be very intelligent observations.

I don't think your observations of the IT world are any different on this side of the world.

The educational observations are also similar, but while they teach ICT here, mostly its not going to help get programmers.

IMO Too many schools/teachers are using IT devices to teach rather than as a tool, and the basics or underlying concepts are being missed.

So my question (ignoring what the pen pushers say)

If you were to introduce computing/programming to 10-13yr olds, what would you teach?

For arguments sake .... lets assume you will be using either a Pi or BBB since it has external capabilities, and is affordable.

Would you start with a generalisation of the CPU, memory, etc and how it connects to the HMI bits.

Do you then jump to the software and how it uses the hardware to perform its tasks.

How much about the hardware do you need to teach, in order to achieve something on screen.?

Do you get into detail about the OS and how it works. (using one of the recommended/supported OS's)

What flavour of programming do you teach/introduce  ... Python/C or something else?

(Bearing in mind this is a beginning class and not a full time study at varsity)

Do you start with drag and drop (ie scratch) and hope they move on.?

Do you make it longer than one period (ie 1.5hrs) spread over a number of weeks, or do you get better traction with a full day.?

as a background

I'm not a teacher, and not a software programmer. (more like a ... dabbler)

I have introduced some pupils at my local school into Arduino.

I also support a program that introduces electronics to Year 7/8 and they get to make/program and take home a Xmas Tree.

http://www.element14.com/community/blogs/pdp7/2012/01/24/merry-birthday-to-you#comment-17591

Hence I'm interested in the thoughts.

Mark

coder27 wrote:

 

User Dio made a comment related to this, and Clive responded:

... I don’t see any “glaring errors” myself, just different ways of talking about a topic to a specific audience. (We call this “teaching” )

Ugh.  Explaining things in such a way that some people see "glaring errors"  isn't called "teaching", it's called being ambiguous, obscure or possibly incorrect.  And if it's the case that the student is mistaken, then dismissing it with a joke isn't called "teaching" either, it's called being unhelpful and leaving the student without comprehension.

Hopefully it was just an uncommon blip.  Teachers must engage.

I wouldn't know enough about teaching, but when I think about what I was taught, I think what inspired me and quite a few people I knew to begin having an interest in Engineering (even if some did not pursue a career in Engineering), a few things that stick out  all seem to have been concerned with some big picture, or an interesting goal. For example, building a model vehicle as part of a team, or learning drawing from a teacher who was a draughtsman in WW2, or a visit to see inside Concorde, etc. Not everyone would be interested in the same thing, but it gets creativity flowing, or a desire to learn. Some people went to see Concorde just to have a day outside the classroom, but I think they would still remember some interesting engineering-related things about it. Now there are some quite inspirational films and movies too - Apollo 13 and October Sky spring to mind. I don't know if such contrived examples as a blender help. But I'm no expert. This photo (source site) makes it clear that that the light-blue robot fetches data for the CPU, and that the green robot stores in registers, and the dark-blue robot reads from the program ROM.

Mark,

If you were to introduce computing/programming to 10-13yr olds, what would you teach?

First of all, I first learned programming in 10th grade, and never felt like I wished I had learned

it sooner.  In that sense I think it's different from learning a musical instrument.

I would want the students to be mature enough to be able to read a language tutorial.

There are some concepts like variables, and operator precedence (2+3*4)=14, not 20,

that are shared with algebra, so I'd want to build on a solid understanding of algebra.

I think Pascal is a decent teaching language, because you can read the entire reference

manual, the compiler doesn't do too many things behind your back, and many errors

are detected at compile time or with run-time checks.

I think you can start at any level of abstraction you think is interesting.  You can show

how to make a half-adder and full-adder out of logic gates, or you can teach base-2 arithmetic,

or you can teach assembly language programming, or you can teach python programming,

or you can teach html and javascript web design.  And I don't think it matters much what order

you teach such topics.

I don't know anything about teaching electronics.

I think calculating prime numbers by trying all possible divisors makes a good first project,

assuming the students know what a prime number is.  I gave some other suggested topics here:

http://www.element14.com/community/thread/23494?start=2&tstart=0

What I _wouldn't_ do in the first few lessons is try to teach GCSE 2.1.1

(d) explain the need for adherence to suitable professional standards in the development, use and

maintenance of computer systems

(e) explain the importance of ethical, environmental and legal considerations when creating

computer systems.

Morgaine Dinova wrote:

Hopefully it was just an uncommon blip.

I suggest you don't read the rest of the comments coder27 has been quoting from then. I gave up quite quickly.

I didn't read the GCSE syllabus, or watch the videos, but I find it interesting that they appear to be slavishly following what I'll call a 'specification' and thinking everything's ok... While others are pointing out the spec may well be flawed.

I see similar stuff where people will, to some degree justifiably, close bugs with comments along the lines of 'works as designed' while completely ignoring that the design and the spec it was built from are obviously flawed if not simply wrong.

Shabaz

Thanks for your insight, and yes the little robots help explain easily ( a picture is worth 1000 words)

I agree there needs to be some bigger picture in order to want to get there.

Coder27

Thanks

One question 10th grade ? what year/age is that

Here we go to school at age 5, and that is considered year 1 (it had other names back in the days I went, so I still have to work it out)

I forgot about the post, and yes there are some good examples there .... thanks

Luckily we have no knowledge of GCSE , and it looks like that is a bonus.

Mark

One question 10th grade ? what year/age is that?

about 16.

Luckily we have no knowledge of GCSE , and it looks like that is a bonus.

Yes, definitely.   It appears to be completely uninspiring.

I'm surprised the RPF is slavishly following it.

Mark Beckett wrote:

 

If you were to introduce computing/programming to 10-13yr olds, what would you teach?

Difficult question, but I think John's answer of "Logic" is a good place to start.

You have to be careful about getting into a lot of hardware details at that age, it's likely to have changed several times by the time they get to university.

It becomes a bit easier once they're old enough to pick their own subjects, but before that you need to keep it general enough to be interesting and not send 85% of the class to sleep.

Mark Beckett wrote:

 

If you were to introduce computing/programming to 10-13yr olds, what would you teach?

Difficult question, but I think John's answer of "Logic" is a good place to start.

You have to be careful about getting into a lot of hardware details at that age, it's likely to have changed several times by the time they get to university.

It becomes a bit easier once they're old enough to pick their own subjects, but before that you need to keep it general enough to be interesting and not send 85% of the class to sleep.

selsinork wrote:

 

Difficult question, but I think John's answer of "Logic" is a good place to start.

 

I just had an idea (don't know how feasible with kids) - what if each student had to be one of the robots, so no one person knew what the end program did, until they saw the result.

Or, taking the idea of logic, each student becoming a particular logic gate, and when they are handed (say) two colored balls (or something else to represent 1's and 0's), then they pass the resultant colored ball to the next logic gate.

Maybe that's too dumbed-down and tedious after a few minutes of it though..

The falstad simulator is incredibly flexible, here is an example. It can be totally modified by dragging wires, or right-clicking to add gates.

It covers other topics too, such as this example (might want to turn the volume down a bit first).

I just noticed this PDF from the University of Auckland is using that simulator for some coursework.

I wonder if anyone has written exercises for younger students based on this simulator - it is quite nice since no special software is needed.

shabaz wrote:

 

Or, taking the idea of logic, each student becoming a particular logic gate,

I'm not 100% sure what John had in mind, but I wasn't meaning logic quite so literally.

The falstad simulator is incredibly flexible, here is an example. It can be totally modified by dragging wires, or right-clicking to add gates.

I suspect that's a bit too far for 10-13 year olds, but I could be wrong.

Teach the principles of logic or at best simple single and/or/not operations, leave the descent into boolean algebra for later.

Sorry you're right.. I still had GCSE's in my head.