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Why Raspberry Pi Is Unsuitable for Education

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Re: Why Raspberry Pi Is Unsuitable for Education

#61

Post by talmand »

judofyr wrote: post #44
jiggy2011 wrote: post #33

Earlier quoted context omitted.

He said "education" with any further qualification. I'm not even sure that the pi was developed with the intention to teach "low level" stuff.

> He said "education" with any further qualification. Sure. And the Hacker News crowd loves people who point out statements that are not strictly true. Hey, who cares what the author actually meant, this line here is wrong !

I would agree, except that this is the title of his post. You have to read a bit into the post to realize that what he's talking about has very little to do with what his title states. A very generic term was used when the intention was for one very small niche of "education". After reading the article the title suggests that because it might be difficult to write a graphics driver for a somewhat undocumented chipset then the whole thing is unsuitable for teaching a kid something like, let's use Python since someone else mentioned it.

If it's not wrong then it's misleading.

Re: Why Raspberry Pi Is Unsuitable for Education

#62

Post by astrodust »

fnordfnordfnord wrote: post #43

It cost thirty bucks. My students (who wrote their first computer program last semester) had it up and running within the first hour after it was delivered. Two weeks later and they have a wifi controlled skid-steer robot prototype running using the Rasp. Pi, Arduino, some proprietary motor controllers, a PS3 controller and PyGame. Now they are refining their code/design, improving it. They spend so much time working…

All this without VHDL source code? What the heck is the world coming to!?

Re: Why Raspberry Pi Is Unsuitable for Education

#64

Post by zxcdw »

jaggs wrote: post #57
DanBC wrote: post #41

Earlier quoted context omitted.

>These days there is just simply no suitable platform to actually play around with Have you seen the Maximite computer? ( http://geoffg.net/maximite.html ) Searching HN shows several references (a couple from me) about this interesting device. It should be really easy to emulate a Z80 / 8080 era CPU with nice graphical outputs for address lines and everything else. And being emulated means that single-stepping this d…

>These days there is just simply no suitable platform to actually play around with http://www.redferret.net/?p=33596

That is very different from what old 8-bit home computers are like. You have complete control over the system, you can write self-modifying code, you can overwrite parts which are used by the OS to manage graphics modes and so on. There are no restrictions, it's just a bunch of ROM and RAM and no limitations.

All I can do on a Raspberry Pi I can do by installing a Linux distribution on my laptop. It's exactly the same thing, and infact it's far easier by using available x86 hardware.

The whole essence is to simplify things so much that you can really go down to the real metal. direct framebuffer access, direct memory address dereferences, instant crashes upon doing something stupid.

Say you buy an used C64, plug it in your TV and turn it on. What's the stuff you are presented to? 5 lines of greeting text and a BASIC prompt! You immediately get to write code the exact moment you turn the thing on! How cool is that!? No installing software, no getting keyboard or mouse, nothing. Just connect the thing to the TV and the power cord to the wall and you're good to go. Of course the machine comes with user manual explaining the various CPU features and BASIC language and so on, very simple. Nothing equivalent to this is offered these days(although the demand for such is lower too, understandably).

Re: Why Raspberry Pi Is Unsuitable for Education

#65

Post by ChuckMcM »

Its an interesting rant. I've maintained for a while that the amount of encumberances in a modern SoC exceed their value for all but a few. But here is the thing, you could still go out and build a CP/M machine, yes Z80's are still for sale [1], you can't really build a floppy disk controller these days but you can simulate one with MMC/SD cards. But the question which is not well specified is what are you trying to teach?

The typical computer science curriculum from the 80's involved learning programming with PASCAL or C, a bit of Assembly, then Compiler Design and Data Structures, followed by Data bases, operating systems, and if you were lucky distributed systems. Along with a healthy portion of set theory, complexity analysis, algorithms, and logic.

The key is that very little of the typical Computer Science degree involved actually writing a device driver or looking at the code of one. It was more about what the role of a device driver was in abstracting what hardware could do into easily used function calls or object methods.

If there was a cheap 'terminal' you could do most of that with a very inexpensive board (even a soft-CPU if you wanted). I've been working intermittently on exactly such a system, perhaps the next time I take a break from working full time I'll finish it, I doubt the development of such a system would be particularly profitable (even as a 'lifestyle' business).

But the point of this response is that to rant effectively you need to state the problem, and I don't think the author here does that, what learning is prevented by the restrictions on the Pi? What percentage of all the learning you might do is that? Who is effected? None of those questions are explored. I really liked Limor's response (LadyAda) which went to the things you could do rather than focus on what you could not do.

[1] http://www.digikey.com/product-detail/en/Z84C0006PEG/269-389...

Re: Why Raspberry Pi Is Unsuitable for Education

#66

Post by Someone »

rwmj wrote: post #58
gaius wrote: post #48

Earlier quoted context omitted.

I dunno, they came enough schematics that you could interface anything you wanted to the user port and read/write to it with what we now call memory mapped I/O. RS232 was a universal standard, the most you would have to do is physically make up a cable. Both the Beeb and the C64 came with a manual that explained to you how to patch the OS (via vectors). On the C64 you could even switch the entire OS out and get its e…

The original article wants the equivalent of an open source Z80/65xx/68k, fuse settings for all the ULAs, schematics for all custom-designed chips, and open source ROM disassemblies. 1980s home computers didn't come with these, even though they had (for the time) very powerful custom graphics and sound chips (eg. Amiga [1]). Of course, some of it was reverse engineered, and some of it has been released long after the…

1980s home computers maybe did not, but one cannot not claim Apple was locking you in in 1978. I think ftp://ftp.apple.asimov.net/pub/apple_II/documentation/misc/a2_reference_manual_alt.pdf shipped with every Apple ][. It seems to contain enough information to clone the machine (electronics diagrams, timing diagrams, ROM disassemmbly, etc.)

Re: Why Raspberry Pi Is Unsuitable for Education

#67

Post by Flenser »

RobAley wrote: post #5

> Also, if you want the Foundation to send more documentation to you, they require you to provide a business model. No they don't. That section talks about broadcom, who are the ones who you will need to give business info to to buy the chips. The foundation don't manufacture, sell or provide documentation for the chips.

What's worse is that "provide a business model" is a link to the FAQ[1] which says it's broadcom:

But I demand the documentation for the chip. Give it to me!

To get the full SoC documentation you would need to sign an NDA with Broadcom, who make the chip and sell it to us. But you would also need to provide a business model and estimate of how many chips you are going to sell.

[1] http://www.raspberrypi.org/faqs

Re: Why Raspberry Pi Is Unsuitable for Education

#68

Post by drbawb »

jlgreco wrote: post #51
zxcdw wrote: post #35

I can almost relate. Consider comparing Raspberry Pi to say Commodore 64 or ZX Spectrum. Anyone familiar with programming 8-bit home computers of the 80's knows how simple they were by their hardware and how easy it was to grasp them. What was(and still is) great about them, is that any kid(regardless of age, as long as they can read) was and still is able to learn how the computers work . How many kids these days ge…

When I was a kid I got my indroduction to programming on TI graphing calculators. They are unfortunately expensive (though pretty much every American school has boxes of them sitting around already) and lack the pinouts that Arduinos have (there is an IO port which isn't great, and USB which... is ok.) but they are otherwise fantastic for this purpose. The TI-BASIC on them is dreadful slow so after you cut your teeth…

I also learned on a TI-83 (handed down from my sister) and a TI-92 (from the boxes at school).

However, I much preferred my HP-50g, USER RPL was an absolute dream to program in, the USB interface was fantastic, an emulator was readily available, and you could even write applications in C and cross-compile them for the calculator.

That and RPN with a multi-line display and an [virtually] unlimited stack is the "one true way."

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