New Raspberry Pi Model B+ - Page 1
Forum section: electronics / general

author: rolycat
author_rank: Super Contributor
timestamp: July 17, 2014, 10:31:25 am
content: In case anyone hasn't seen it yet, the Raspberry Pi foundationannounceda new version of their single board computer this week:It has loads of improvements including more USB ports, lower power consumption and more GPIO pins.Still made in the UK and still $35.

author: bwat
author_rank: Frequent Contributor
timestamp: July 17, 2014, 11:04:16 am
content: Quote from: rolycat on July 17, 2014, 10:31:25 amTwo of the most talked about products in this market are made(*) in Europe and both are quite affordable for those living in the countries of manufacture. I get the feeling that my perception of the economics of electronics manufacture doesn't quite match reality. I seem to believe that it just cannot be done unless it is manufactured in low cost countries. Obviously this isn't the case.*)made/assembled/whatever.

author: bwat
author_rank: Frequent Contributor
timestamp: July 17, 2014, 11:14:40 am
content: Quote from: wilfred on July 17, 2014, 11:12:20 amTry the link the OP gave.

author: GeoffS
author_rank: Unknown
timestamp: July 17, 2014, 11:39:47 am
content: +1 for four mounting holes.No need for the hot glue gun any more

author: firewalker
author_rank: Super Contributor
timestamp: July 17, 2014, 12:11:36 pm
content: It will be nice a 1 Gbyte RAM version.Alexander.

author: AndyC_772
author_rank: Super Contributor
timestamp: July 17, 2014, 12:18:54 pm
content: I wonder whether it'll end up like the BBC Micro model B+, from which it draws its name?The B+ was supposed to be an improvement over the hugely popular Model B, but in practice the fact that it just wasn't quite thesameas a Model B made it unpopular despite the technical improvements.The software compatibility problems that came from its added memory and different floppy disc controller outweighed their usefulness, and it wasn't until the (much *more* different) Master series that these changes really became accepted by users are were properly supported by software. The poor old B+ never really got past the chicken-and-egg stage when it came to sales vs support.

author: bwat
author_rank: Frequent Contributor
timestamp: July 17, 2014, 12:23:26 pm
content: Quote from: AndyC_772 on July 17, 2014, 12:18:54 pmI would take a beeb over a raspberry pi any day. Serious!

author: rob77
author_rank: Super Contributor
timestamp: July 17, 2014, 01:32:58 pm
content: Quote from: firewalker on July 17, 2014, 12:11:36 pmit's still 512Meg. a colleague of mine has ordered it from Farnell and he's got it already. it's a nice board with a much better layout than the original B.it has a microSD slot . the microSD card is "sticking out" approx 2mm from the board - therefore the microSD can be completely hidden and still accessible through a gap in the wall of the case if you'll have a case with wall thickness of 2-3mm.in general it's well designed for embedding into products (compared to the original B).

author: tszaboo
author_rank: Super Contributor
timestamp: July 17, 2014, 02:11:32 pm
content: While it is an improvement, I still dont understand why the connectors are scattered on two sides, and why we didn't get back the I2S port.

author: rob77
author_rank: Super Contributor
timestamp: July 17, 2014, 02:30:24 pm
content: Quote from: NANDBlog on July 17, 2014, 02:11:32 pmsize is the limitation for 1 sidebut anyways - 2 sides with connectors is acceptable - if you want to place it into a bigger case, then you just place it to the corner and make the cut-outs for the connectors on 2 sides of the case (that was not possible with the original B with connectors on all 4 sides).

author: Precipice
author_rank: Frequent Contributor
timestamp: July 17, 2014, 02:59:35 pm
content: Quote from: bwat on July 17, 2014, 11:04:16 amIf you're manufacturing something like this in volume, you don't need many people to run the line - it's mainly the cost of the machines, which is roughly the same globally, and some factory space, which isn't too bad, especially in Wales.Inserting dozens of screws into a phone, lining up fiddly connectors, polishing shiny things - they all take huge amounts of effort, and go where the people are cheapest. Manufacturing operations that are un-green also tend to offshore to countries that worry less. SMT assembly is pretty green - energy in, packaging waste out, and there's decent recycling routes for most of that - although I don't know where the paper tape and cover tape from reels of passives ends up. Should burn well enough, I guess...(UK manufacturing is still pretty healthy - it's less dominant than it used to be, because services have increased faster than it, rather than manufacturing declining, although headcount has fallen (continuously, I think?)).

author: BloodyCactus
author_rank: Frequent Contributor
timestamp: July 17, 2014, 04:40:34 pm
content: i know the B models had issues with usb throughput with just 2 connections.. sure lets add 4! ugh. gpio is like a shotgun, pins all over the place. it would have been nice when going from 26 to 40 pin connector they re-arranged all the pins into a logical order.very nice to see mounting holes!

author: rolycat
author_rank: Super Contributor
timestamp: July 17, 2014, 04:47:19 pm
content: Quote from: BloodyCactus on July 17, 2014, 04:40:34 pmLots of people want to attach a keyboard and a mouse, which are low-bandwidth peripherals, plus a wireless dongle and maybe from time to time a memory stick. Throughput shouldn't be much of an issue in the most common use cases.QuoteBut that would have made all of the existing plates and other peripherals incompatible, instead of just a few.Always choices to be made, but I think they made the right ones.

author: GeoffS
author_rank: Unknown
timestamp: July 17, 2014, 04:51:36 pm
content: I run a couple of Model B's as weather cameras with a wifi dongle and a USB hard disk, makes trouble shooting a lot easier if you can plug a keyboard in.

author: motocoder
author_rank: Unknown
timestamp: July 18, 2014, 02:24:29 pm
content: Quote from: rolycat on July 17, 2014, 10:31:25 amIt looks like a nice incremental improvement, although I've sort of soured on the Raspi since that bad experience with their camera board and the rabid attacks I was subjected to for pointing out low light issues and suggesting USB webcams were a good alternative... Will stick with BeagleBone Black for the foreseeable future.

author: rolycat
author_rank: Super Contributor
timestamp: July 18, 2014, 03:22:09 pm
content: Quote from: motocoder on July 18, 2014, 02:24:29 pmNot sure I understand this.If by "rabid attacks" you meanthisthread, then I would agree that 'jamesh' was inexcusably rude in his initial response to your post, but it seemed as though it was all resolved fairly amicably. A nasty response from one grumpy engineer doesn't seem like a good reason to abandon the platform altogether.I don't frequent that forum however, so I may not have all the information. Were there other attacks?

author: Richard Crowley
author_rank: Super Contributor
timestamp: July 18, 2014, 03:49:38 pm
content: I also wasn't terribly impressed by the RasPi website or the forum.The website has nice eye-candy and flash, but organization and presentation of hard facts, specs, and data is in short supply.And the forum just leaves me cold. It seems unwelcoming to newbies and also disorganized. They have a great deal to learn from Arduino.The chaotic nature of the website and forum seem surprising to me given the number of boards out there.But the new B+ module has most of the things I thought were sorely absent in the original board.

author: amyk
author_rank: Super Contributor
timestamp: July 19, 2014, 01:17:07 am
content: Quote from: Richard Crowley on July 18, 2014, 03:49:38 pmIt's Broadcom, what'd you expect? Ask for more detailed information (e.g. GPIO rise times) and you'll be told in a very roundabout way, "no". (They'll try to play the "you don't need to know", "it's too complicated for you to know", etc. lines - these are people wanting to learn.) Try asking harder and they'll just lock the thread. The forums are highly moderated to suppress any straying from the official line.That camera thread is just.... He's basically advocating vendor lockdown.'jamesh' is a total prick in many of his other posts on the forum too where people ask for more information.All this, in a board designed foreducation, justdisgusts me beyond belief and makes me think the whole thing is just marketing for Broadcom.</rant>Arduino is much better in that full documentation is available, you can use as much or as little of it as you want and won't be told otherwise. But the best computer for education is just a standard PC - tons of them are getting thrown away every day in fully working condition(!), many of them far more powerful than the Pi, and you can find far more information about programming PCs from low-level hardware and up, plus there's lots of software available. Even open-source BIOS replacements are available. Parallel ports (which are going to be common on old hardware, the type that's being discarded) make great GPIOs.If you want a cheap ARM-based devboard, I'd say go for one of the Chinese SoCs -AllWinner make some pretty decent ones.

author: motocoder
author_rank: Unknown
timestamp: July 19, 2014, 01:21:28 am
content: Quote from: rolycat on July 18, 2014, 03:22:09 pmThere was quite a bit more than the one post in the forum from Jamesh, but quite frankly I have no desire to go back over there and revisit it.The gist of it was, "you are hurting a charitable project by 'criticizing' one of its features". The whole thing was asinine, as my intentions were a) to point out the problem so they might fix it, and b) to point out that USB webcams work great with the Pi, so that others with similar requirements might be successful. I was as delicate and nice about it as humanly possible.Jamesh, and to a lesser extent James, started out defensive, and then basically clammed up when I posted info showing the actual problem (including light meter readings, photos) and when others chimed in reporting the same issues. At no time did I detect any interest in following up with me or anyone to gather data to help determine the actual issue. Just a bunch of butthurt babies.I wish them all the success in the world, but I'll send my business elsewhere. Plus, I really prefer TI products over Broadcom. I don't like that most of the data on the Broadcom part is not freely available.

author: max-bit
author_rank: Frequent Contributor
timestamp: July 21, 2014, 05:43:17 am
content: And they could add 1GB of RAM?

author: rob77
author_rank: Super Contributor
timestamp: July 21, 2014, 08:44:05 am
content: Quote from: max-bit on July 21, 2014, 05:43:17 ami think that would require a serious redesign - they're mounting chips one on a top of the other (CPU + RAM), so most probably a bigger RAM chip simply doesn't fit.

author: Psi
author_rank: Super Contributor
timestamp: July 21, 2014, 08:56:49 am
content: Quote from: rolycat on July 17, 2014, 04:47:19 pmYou mean i cant connect 4 ezcaps and save four uncompressed video streams

author: bwat
author_rank: Frequent Contributor
timestamp: July 21, 2014, 09:39:55 am
content: Quote from: amyk on July 19, 2014, 01:17:07 amExactly! I've said similar things here myself -https://www.eevblog.com/forum/beginners/advice-for-novice/msg468376/#msg468376. I apologise for hijacking the thread to boost a message I feel is quite important.

author: rob77
author_rank: Super Contributor
timestamp: July 21, 2014, 10:37:14 am
content: Quote from: bwat on July 21, 2014, 09:39:55 amand how the hell would you teach interfacing hardware with a standard PC ? RPi is ideal - it runs a widely known OS, has GPIO and has high-level language libraries/bindings for the IO.

author: bwat
author_rank: Frequent Contributor
timestamp: July 21, 2014, 10:45:26 am
content: Quote from: rob77 on July 21, 2014, 10:37:14 amI think this side discussion maybe needs a new thread.

author: rob77
author_rank: Super Contributor
timestamp: July 21, 2014, 11:15:24 am
content: Quote from: wilfred on July 21, 2014, 11:10:41 am+1

author: Richard Crowley
author_rank: Super Contributor
timestamp: July 21, 2014, 02:02:54 pm
content: Quote from: amyk on July 19, 2014, 01:17:07 amWell, I'm OK with the proprietary information about the internals of the Broadcom chip, but their attitude seems much more like "you don't need to know" or "it's too complicated". If that is their attitude, then they are selling low-end toys and I am interesting in something more substantial. Publishing more advanced and detailed information does NOT eclipse the "dumbed-down" version they publish for newbies. But their attitude seems like "you are all just dumb users and you can't handle the adult version". Bah!

author: senso
author_rank: Frequent Contributor
timestamp: July 21, 2014, 03:08:19 pm
content: Wasn't the legal excuse that you could reverse engineer the chip if you had access to the datasheets.What strikes me is that chip is/was used in consumer products, how comes no one leaked a complete or more complete that the actual released datasheets?

author: amyk
author_rank: Super Contributor
timestamp: July 22, 2014, 09:18:15 am
content: Quote from: rob77 on July 21, 2014, 08:44:05 amThe RAM chips are in a standard 168-ball PoP package, they don't physically change size with capacity - only the die internally is higher density.The SoC supports 1GBso it would be easily doable - and 8Gb (1GB) parts are available, but apparently too expensive for their budget. One I could find is theNT6TL256T32AQwhich is ~$10 a piece in 10k quantities.QuoteStandard PCs have parallel ports, you can use those as GPIOs pretty easily - they're also specified to be 5V-tolerant.QuoteWhat's cheaper, more open, and has more available software than an RPi? A perfectly working PC that's been throw away (people really do this). Nothing beats free, and it'll probably be a lot faster than the RPi too.QuoteBecause it's Broadcom.

author: rob77
author_rank: Super Contributor
timestamp: July 22, 2014, 10:15:56 am
content: Quote from: amyk on July 22, 2014, 09:18:15 amthe $10 is a no-goand probably heat-dissipation would be a no-go as well - even if the 8Gb (1GB) chip has the same package.today's standard PC has no parallel port anymore , and even if it had - teaching kids to interface LEDs and buttons with paralel port is not the best approach.

author: bwat
author_rank: Frequent Contributor
timestamp: July 22, 2014, 10:29:47 am
content: Quote from: rob77 on July 22, 2014, 10:15:56 amWhy not?Sample code for parallel port IO:Setup for readingCode:MOV AL, 20HMOV DX, 37AHOUT DX, ALRead a byte and load it into register ALCode:MOV DX 378HIN AL, DXSetup for writingCode:MOV AL, 00HMOV DX, 37AHOUT DX, ALWrite the byte in register ALCode:MOV DX, 378HMOV AL, DATAOUT DX, AL

author: rob77
author_rank: Super Contributor
timestamp: July 22, 2014, 11:44:59 am
content: Quote from: bwat on July 22, 2014, 10:29:47 amok. congrats ! you know some assembly.now tell me how the hell would you run than on a modern OS... probably you didn't notice... but it's 2014 here ! no MSDOS, no printer ports !furthermore why the hell would you teach kids something what's not usable (code in assembly for a modern OS) and not available (LPT port)?high level language and hardware suitable for the job is the way of teaching kids. a kid needs to see a result with minimal effort in order to maintain the level of interest and focus

author: rolycat
author_rank: Super Contributor
timestamp: July 22, 2014, 11:49:23 am
content: Using old PCs may be a cheap way for an individual child to learn about computer interfacing and low-level programming, but it would be a nightmare for a teacher with a classroom full of kids.There might be plenty of PCs at school, but the IT department are unlikely to appreciate unknown and possibly destructive voltages being applied to their parallel ports, even if they still have them.And how is a teacher supposed to manage a class with twenty different PCs at home sporting half a dozen OS variants, some with parallel ports, some without, and a bunch of kids whose parents couldn't be bothered to find them an old machine?Even if somehow all of those problems could be overcome, parallel ports have a number of disadvantages. A selection:No power railOnly five input and four bidirectional pinsVarious pins are hardware invertedNo A/D capabilityNo I2C or SPI without bit-bangingTricky to access from modern versions of WindowsThey can all be overcome with effort and ingenuity, but it's hardly intuitive.PS8086 assembler?

author: bwat
author_rank: Frequent Contributor
timestamp: July 22, 2014, 12:37:25 pm
content: Quote from: rob77 on July 22, 2014, 11:44:59 amIt wasn't done to show off. It was a clear demonstration of how easy it was to manipulate the parallel port on a PC.Quote from: rob77 on July 22, 2014, 11:44:59 amYou don't need an OS. If your program is less than 510 bytes then you can stick it on a USB disk, reboot the machine and have the code executed. For development and debug just use BOCHS. See the filebuild.x86/mbr.Sin the source code to thislittle kernelQuote from: rob77 on July 22, 2014, 11:44:59 amNot useable? I've been paid good money to write assembly code. As for the printer port, please reread the original suggestion given earlier.Quote from: rob77 on July 22, 2014, 11:44:59 amI was taught 6502 assembly as a kid. We hand assembled and punched the machine code in, nibble by nibble, on a keypad then pushed the run button. Strangely we didn't lose interest or focus.

author: bwat
author_rank: Frequent Contributor
timestamp: July 22, 2014, 12:45:11 pm
content: Quote from: rolycat on July 22, 2014, 11:49:23 amI think this is the point that is trying to be made. The thing is that the same machine can be used to teach a whole CS curriculum.Quote from: rolycat on July 22, 2014, 11:49:23 amIf you're going to teach low-level then assembly language should be taught too IMHO. PCs are everywhere so 8086 is as good a choice as any.

author: rob77
author_rank: Super Contributor
timestamp: July 22, 2014, 01:04:30 pm
content: i'm not saying it's not possible... but we're talking about teaching kids... there are few of them enjoying to go deeper and getting even more interested when things get more complicated , despite the lack of actual positive results during the process (i guess it was your case as well) , but the majority of kids are like "does it work in 10 minutes ? no ? that's boring shit, i rather try something else".btw... when i was a kid/youngster i was coding Z80 and 8080 without using assembly - directly writing code in hex-editor ( a hex editor written by myself) just because i was able to do it and it was much faster than writing the code in assembly and then compilebut i'm not expecting that everyone else is able to do it, and i'm not even suggesting to do it that way - because for the majority of people it's way too complicated to learn all the opcodes for the whole instruction set (and in fact it's waste of time to learn that).so the fact that one person is able to do something doesn't mean that everyone should do it that way, and it definitely doesn't mean it's the right way of doing that thing...so in fact the RPi is close to ideal for teaching kids how to interface HW - you get everything you need - a small computer with OS a highlevel language interpreter and libraries for easy manipulation of the GPIO pins. the kids are able to make a LED go blinky-blinky in 5 minutes (hook-up the RPi to a breadboard, stick in a led + resistor, write very few lines of python code and bob's your uncle), they'll see an actual result very quickly and there is a bigger chance that they'll get interested even more and dig deeper.

author: rolycat
author_rank: Super Contributor
timestamp: July 22, 2014, 01:05:43 pm
content: Quote from: bwat on July 22, 2014, 12:45:11 pmWhich 'same machine'? A PC? There are tens of thousands of variants, as I pointed out. Modern PCs are totally unsuitable for low-level work and old PCs are totally unsuitable for classroom work, as I also pointed out.The whole reason why Eben Upton created the Raspberry Pi was because today's kids see computers as sealed boxes for accessing the internet and playing games. Very few people look at a modern laptop or tablet and think "Hey, I could reprogram that to control a bunch of LEDs". And kids see old PCs for what they are: yesterday's obsolete technology. They're not interested.QuoteQuote from: bwat on July 22, 2014, 12:37:25 pmYeah, and Space Invaders was a craze in the 1970s. Try getting a modern kid excited about some crude pixelated blobs going bleep bleep bloop. (Unless they programmed the blobs themselves).Times change, and education has to change with them.

author: bwat
author_rank: Frequent Contributor
timestamp: July 22, 2014, 01:37:27 pm
content: Quote from: rolycat on July 22, 2014, 01:05:43 pmNo they're not. I develop my operating systems on modern PCs. I think they're quite suitable for low level work.Quote from: rolycat on July 22, 2014, 01:05:43 pmAnd I wrote that this wasn't the point being made. I was talking about the "individual child" as you put it.Quote from: rolycat on July 22, 2014, 01:05:43 pmDo you think this worked? The raspberry pi and the blinkenlights-for-the-kids marketing is part of the problem.Quote from: rolycat on July 22, 2014, 11:49:23 amThings have gotten worse. There was a time when the focus wasn't learning to program but programming to learn, as described in these books:Mindstorms, PapertTurtle Geometry, Abelson and DiSessaJust look how computers were being used in education back in London:http://link.springer.com/article/10.1007/BF01908616#page-1http://books.google.se/books?id=oqqoUMj9-pUC&pg=PA527&lpg=PA527&dq=imperial+college+prolog+schools&source=bl&ots=j2Gi4s7CCC&sig=vyO4MnTfXG5WZYNmXWRydHQYtIc&hl=sv&sa=X&ei=SmLOU67NGoqGywPX0oC4Cw&ved=0CDIQ6AEwAg#v=onepage&q=imperial%20college%20prolog%20schools&f=falseFrom the New Scientis article linked above:QuoteThat's an 11 year old using a mechanical theorem prover for the Horn clause fragment of first order predicate logic tobuild an electronic phrase book!

author: rob77
author_rank: Super Contributor
timestamp: July 22, 2014, 01:53:56 pm
content: @bwati think we all got the message by now

author: rolycat
author_rank: Super Contributor
timestamp: July 22, 2014, 02:12:35 pm
content: Quote from: bwat on July 22, 2014, 01:37:27 pmThe context was the education of the current generation of children, not the abstruse technological obsessions of old farts like you and me.QuoteContext again. Teachers cannot have a different lesson plan for each child.QuoteIt's not really being used for formal education yet, but I think it will work better than your plan to let them all duke it out with a random collection of ancient hardware.To a degree the foundation have been a victim of their own success - the original intention was to produce a few thousand units for enthusiasts and early adopters while they worked on a complete education package, which hasn't yet been completed.But overall I think it's working really well for mere mortals. If you believe achievement should be hard-won even for children and complete novices you may disagree.QuoteDo you think this worked?Before you jump to the keyboard with yet another rebuttal, consider an interesting phenomenon called the backfire effect. It's a corollary to confirmation bias and means that when strongly held beliefs are challenged, opposition makes people even more intransigent. Cogent arguments against their theory are dismissed in favour of ever wilder justifications for their obsession.Everybody suffers from it, but when most of the world agrees on a subject and you are one of the few defenders of an unpopular view, it would be well to open your mind just a little in case you are not the contrarian genius you think you areBefore someone else does I should mention that if you open your mind too much your brain will fall out

author: Rigby
author_rank: Super Contributor
timestamp: July 22, 2014, 06:54:28 pm
content: Quote from: max-bit on July 21, 2014, 05:43:17 amNo, they're already at the RAM limit. There aren't enough pins left on the chip to address more RAM. That Broadcom chipset can't go higher than 512MB.

author: rolycat
author_rank: Super Contributor
timestamp: July 22, 2014, 07:18:07 pm
content: Quote from: Rigby on July 22, 2014, 06:54:28 pmTake a look atthis link(also provided by amyk above). Some way down the thread, Gert Van Loo - who is a principal engineer at Broadcom - confirmed that it will support up to 1GB:Quote

author: JOERGG
author_rank: Contributor
timestamp: July 22, 2014, 10:33:47 pm
content: It is your choice, there are other optionshttp://en.wikipedia.org/wiki/Banana_Pi

author: bwat
author_rank: Frequent Contributor
timestamp: July 23, 2014, 05:31:57 am
content: Quote from: rolycat on July 22, 2014, 02:12:35 pmYou don't see the irony that this was written by a rapsberry pi apologist? Anyway, your tactic is as bad as that other apologist Rob77 who wrote:Quote from: rob77 on July 22, 2014, 01:53:56 pmIt's the same message: "I don't like what you're writing but I have no argument so I'll just try to force you to shut up". You're both quite "passive aggressive" as the Americans, quite excellently, put it. You're both being weighed down by a strange form of tribalism.Quote from: rolycat on July 22, 2014, 02:12:35 pmYour stated belief that I think I'm a "contrarian genius" is an insult. Granted a mild insult but an insult none the less. I'm sorry I don't like your pet project but when criticism of it means you start insulting people, then maybe there's something wrong!Quote from: rolycat on July 22, 2014, 02:12:35 pmAgain I'll point out in the New Scientist article they writeQuoteThat's an 11 year old using a mechanical theorem prover for the Horn clause fragment of first order predicate logic tobuild an electronic phrase book!

author: ronniegogs
author_rank: Contributor
timestamp: July 23, 2014, 05:57:58 am
content: Just arrived. Fresh out of box. No time to play as I am travelling for Thailand and Malaysia tonight. Will power it on next week.Rasberry Pi B+by

author: neslekkim
author_rank: Super Contributor
timestamp: July 23, 2014, 08:49:31 am
content: Quote from: JOERGG on July 22, 2014, 10:33:47 pmdon't understand why one would make a clone of it, and that price?, I cant find it any cheaper than $65-70, and for that price, I would rater buy one of these:https://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXino-MICRO/open-source-hardwarehttps://www.olimex.com/Products/OLinuXino/A20/A20-OLinuXino-MICRO-4GB/open-source-hardware(that I already bought)Same cpu, but it have lots and lots of GPIO and other nice thing that is sacrified on the bananapi (and raspberry for that matter)Have two rasberry's now, one from the very first batches of the B model (without mounting holes, and 256MB ram), and now the B+ which is an nice iteration.

author: amyk
author_rank: Super Contributor
timestamp: July 23, 2014, 11:26:21 am
content: Quote from: rolycat on July 22, 2014, 11:49:23 amYou think RPis won't get damaged? If anything the GPIO on one is even more fragile than a parallel port. Also, a parallel port card is ~$10 or less - less than half the price of an RPi.QuoteThe nice thing about PCs is that they're standardised - basic things like the addresses for parallel ports are well-known. As for having different OSs, that can easily be solved by giving them a Linux distro to use. For your last point, what about the "bunch of kids whose parents couldn't be bothered to" buy them an RPi?QuotePower supply provides +5, +12 (and +3.3 on ATX if you want to tap into the mobo connector) voltsThe main data pins have been bidirectional since the late 80sSo what?Teaching how to interface an ADC is valuableBit-banging is easy enough, there are libraries to do it anywayUse Linux, as mentioned above, or some other low-level OSQuote...and all he's created is another even more closed system.QuoteThey'll certainly be more interested if you show them what they can do with one.

author: rob77
author_rank: Super Contributor
timestamp: July 23, 2014, 11:43:50 am
content: common guys !do you REALLY want the kids to open the PC to get 5V from the ATX supply ? are you crazy ?if not then please don't make statements likeQuoteand the main point.... once again... THE LPT PORT DOES NOT EXIST ANYMORE ON RECENT PCs ! that's a sheer fact and you should finally accept it !LPT is a IT dinosaur , that's a fact. I personally like the LPT port and i still use it sometimes, but it's simply gone and we have to move forward

author: tjb1
author_rank: Regular Contributor
timestamp: July 23, 2014, 12:22:42 pm
content: Quote from: rob77 on July 23, 2014, 11:43:50 amEh...what?http://www.intel.com/content/www/us/en/motherboards/desktop-motherboards/desktop-board-d525mw.html

author: rob77
author_rank: Super Contributor
timestamp: July 23, 2014, 12:31:36 pm
content: Quote from: tjb1 on July 23, 2014, 12:22:42 pmplease ahve a look at the recent HP and Lenovo PCs (desktops, towers.. whatever)... not to mention that the popular all-in-one PCs got no LPT port from the very beginning.

author: tjb1
author_rank: Regular Contributor
timestamp: July 23, 2014, 01:54:01 pm
content: Quote from: rob77 on July 23, 2014, 12:31:36 pmBecause it is not available on the PCs you purchase from Walmart, Staples, or whatever local electronics store does not mean they don't exist as new technology. They are still made and they still have their use.

author: rob77
author_rank: Super Contributor
timestamp: July 23, 2014, 03:05:36 pm
content: well... let's take a look at ISA bus - boards were still manufactured with a single ISA slot long after it was dead, just to provide compatibility for existing old gear, but the the vast majority of the boards were manufactured without ISA... same happening to the PCI slots nowadays.... and surprise same happening to the LPT ports...sure you'll still find PCs or main boards with LPT port - but it's uncommon or even rare nowadays. there is simply no use for LPT anymore for the ordinary end users - so the manufacturers are saving few bucks by removing the LPT.the primary role of an LPT port was... a big surprise ! connecting a printer ! .. now show me a recent mass produced general purpose printer with parallel interface.... hmm... let me think... there is none ! everything is USB, ethernet or wifi.so teaching kids to interface HW with LPT is useless and hopeless nowadays.

author: tjb1
author_rank: Regular Contributor
timestamp: July 23, 2014, 03:31:42 pm
content: Quote from: rob77 on July 23, 2014, 03:05:36 pmwww.linuxcnc.orgThe world does not revolve around you and what you do, much of the manufacturing world still uses floppy disks and parallel ports.

author: rob77
author_rank: Super Contributor
timestamp: July 23, 2014, 04:34:01 pm
content: Quote from: tjb1 on July 23, 2014, 03:31:42 pmi could say the very same about youhow many idustrial PCs are manufactured per yer ? and how many Personal Computers are manufactured per year ?you see the difference ?and yes i know linuxCNC very well and i also know how difficult is to find a suitable LPT port... many of the PCIe expansion cards with LTP are simply not working with linuxCNC...so accept the fact... LPT is dead when talking about recent Personal Computers..i will not discuss this anymore... live happily in your isolated world and keep ignoring the changes around you if that makes you happypeace for everyone !

author: miguelvp
author_rank: Super Contributor
timestamp: July 24, 2014, 07:05:23 am
content: Even new mobos have parallel headers populated, the thing is that the connector is not exposed on the back.Not sure if anyone cares about the BIOS anymore but there is access to the LPT1 port from the old MS DOS interrupts. And since they are still clones they might still have support for all those INT 17h and INT 21h function 05 (hex or decimal makes no difference on the function 5 since it's the same number).

author: Rigby
author_rank: Super Contributor
timestamp: July 24, 2014, 09:50:38 pm
content: Quote from: amyk on July 23, 2014, 11:26:21 amIt's a lot less "black box" than conventional PCs, and openness really isn't something that students give a rats ass about anyway. The RPi is MORE than open enough to be what it is intended to be.

author: davorin
author_rank: Unknown
timestamp: July 28, 2014, 09:30:41 pm
content: I've used and tried several different boards in the price range between $30 up to $100...Raspberry Pi has just a huge community behind, and what is best, the OS provided just works...so you can start immediately working on your small project...Just this week I got the SAMA5D3 Xplained board from Atmel....nice board I thought...one ethernet with 10/100 and second one with GBit port....Apparently they sell it for quite some time now...so you would think the Linux support should be in the same state as the Raspberry...I still can't get a reliable ethernet connection from the GBit port...some times it works, most of the times not....and I am not alone...The documentation is really poor...Another board I tested (I tested shitloads of boards) was the Riotboard....which is backed by Element14/Farnell...I tried to find the documentation to get a Debian image onto it, as the install process was mentioned on the Element site...But just recently I found out the the blog post from the contributor has been deleted by Element14/Farnell....which is really great!Community and support-wise...Raspberry Pi is a winner.....Performance wise? Never...I rather go with i.MX6 or Jetson TK1 (o;Ah...forgot to mention Beaglebone Black....nice little board....but after several times getting notified by Mouser that the delivery has been postponed againmade me think to switch to other boards and dumped it from my store...

author: Rigby
author_rank: Super Contributor
timestamp: July 28, 2014, 11:25:16 pm
content: I have a few BeagleBone Blacks, and I LOVE these little boards. Worth the wait.

author: amyk
author_rank: Super Contributor
timestamp: July 29, 2014, 11:45:31 am
content: Quote from: Rigby on July 24, 2014, 09:50:38 pmAre you really suggesting the RPi is more open than a standard PC?The amount of technical information you can find about the PC architecture both online and offline (I have over a dozen books...) is absolutely enormous. If students don't "give a rats ass about" openness, maybe they should, because otherwisethey'll never realise the freedom they lost.

author: Rigby
author_rank: Super Contributor
timestamp: July 29, 2014, 12:51:26 pm
content: Quote from: amyk on July 29, 2014, 11:45:31 amOK, fair point, your definition of conventional PC differs from mine, I suppose. What I'm saying is, that it's open enough that no one who is looking for an educational PC needs to worry about exactly how open it is. I'm saying there's value in that, you're saying it's not enough, I think. I disagree with that.