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Why the Raspberry Pi Won't Ship In Kit Form

Soulskill posted more than 2 years ago | from the you-are-too-clumsy dept.

Hardware 240

An anonymous reader writes "A post at the Raspberry Pi blog shows an image containing the device's SoC and memory chip to help explain why the tiny PC won't ship in kit form. Clearly, the chips are so small, and the solder blobs required so tiny, that most people would mess up doing it by hand. Add to that the fact one chip has to sit on top of the other, and if you're a millimeter out, your chips are fried." The post also addresses the use of closed source libraries for graphics acceleration.

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Assumptions (-1)

Anonymous Coward | more than 2 years ago | (#38881735)

I don't like the assumptions they're making.

Re:Assumptions (2)

s0litaire (1205168) | more than 2 years ago | (#38881787)

which are???

Please enlighten us mere mortals....

Re:Assumptions (5, Insightful)

SomePgmr (2021234) | more than 2 years ago | (#38881855)

The only assumption I saw was that most folks would botch assembly due to the teeny smd tolerances. It seems pretty reasonable to me. I don't know a lot of people with reflow ovens or hands that steady. And at $25 & $35 for the assembled models, I don't know why people would really want to.

Re:Assumptions (4, Interesting)

Fned (43219) | more than 2 years ago | (#38881987)

The only assumption I saw was that most folks would botch assembly due to the teeny smd tolerances.

So, anyone who does it successfully would achieve a rare accomplishment, through hard work, diligence, and skill.

I don't know why people would really want to.

You clearly aren't the target market for a kit form, then.

Seriously, though: the world is full of people who want to do difficult, unnecessary things. It is a human-being feature. All Raspberry Pi has to do is say "Kits are not covered by warranty, period."

Re:Assumptions (5, Informative)

viperidaenz (2515578) | more than 2 years ago | (#38882131)

It would probably cost more to package the components for a kit than to assemble the thing anyway, so your kit would not only cost more, it would probably never work anyway.

Your reflow oven would need the correct temperature profile, you'd need a solder paste stencil, you'd also need fresh solder paste of the correct type - because it has an expiry date and should also be kept refrigerated.

Re:Assumptions (-1)

Anonymous Coward | more than 2 years ago | (#38882517)

This is all bullshit reasoning anyway. Instead of BSing (and insulting potential customers in the process) they should just say they do not want to supply kits. Simple really

Re:Assumptions (5, Insightful)

Anonymous Coward | more than 2 years ago | (#38882979)

Really? You don't think the bad publicity they might get if lots of people report "I bought a kit and it failed" is a sufficient reason for them to refuse?

Re:Assumptions (3, Interesting)

Grishnakh (216268) | more than 2 years ago | (#38882921)

It's not that hard to reflow parts. I do it all the time with a toaster oven; basically you turn it on to 200F for a couple of minutes to let the board's temperature equalize, then you crank it up to the maximum, and when it gets there, turn it off and crack open the door to let it cool down slowly.

The problem is that this only works with leaded solder. You need a hotter oven to reflow lead-free solder. But there's not really a good reason to use lead-free solder anyway, so I see it as a non-issue. It's mainly used because some stupid people are worried about kids eating it or something, causing dumb laws to be passed. Simple solution: don't eat your electronics. You don't eat drain cleaner (or let your kids eat it), yet drain cleaner is easily available and no one's banning that, so what's the problem with electronics?

You also don't absolutely need a paste stencil; there are kits available with paste in a syringe with needle; you just squirt a tiny amount onto each pad. Of course, this really doesn't work too well with BGA parts, only the larger-pitch parts and passives. BGA parts, however, shouldn't need any paste; they come with solder balls already installed on the bottom, so you just place them where they're supposed to go, and reflow. There's even reballing kits you can get; I think there was some big problem with Xboxes a while ago requiring this for many out-of-warranty units, and a small cottage industry sprang up with people reworking these boards at home, removing the chip, reballing it, and reflowing it in a toaster oven.

Re:Assumptions (5, Insightful)

Anonymous Coward | more than 2 years ago | (#38882163)

So, anyone who does it successfully would achieve a rare accomplishment, through hard work, diligence, and skill.

And for those ten to twenty people out there? The phrase I'm looking for is "not a significant market".

DIY kit (5, Insightful)

mmontour (2208) | more than 2 years ago | (#38882179)

If you really want a kit you can buy an assembled board, de-solder all of the components, and *make* a kit.

Re:DIY kit (5, Funny)

Anonymous Coward | more than 2 years ago | (#38882969)

It's a kit kit. Brilliant!

Re:Assumptions (5, Insightful)

Anonymous Coward | more than 2 years ago | (#38882195)

The kind of person who can solder BGA are also usually the kind of people who can acquire parts and produce PCBs.

Re:Assumptions (2)

queazocotal (915608) | more than 2 years ago | (#38882747)

You can't actually buy the components involved in small (under 10000) quantities.
In addition, desoldering and attempting to re-ball BGAs is not a good idea.

I'm one of the ones that requested a 'kit' - of the major components - I don't care about the tiny components, those are easy to source.

Why?

Several reasons.
Amongst them:
Because I can (maybe).
Because the r-pi is annoyingly large for some use-cases.
Because being able to trim the design to have just the required bits on can be useful.

Fundamentally - this is about education. Not software, but hardware education.
Fostering a community of interested hardware engineers.

It's a lot easier for many people if in addition to the problems of actually physically constructing the board, (not the actual making the PCB, only insane people would try that), they don't have to do any significant software work to get the board up and working.

Re:Assumptions (1)

Grishnakh (216268) | more than 2 years ago | (#38882949)

You can't actually buy the components involved in small (under 10000) quantities.

Citation needed.

You can get prototype quantities of any electronic part out there. It might be expensive, though sometimes you can get mfgrs to send you samples for free, but how do you think design engineers test their designs?

Re:Assumptions (4, Informative)

RaySnake (607687) | more than 2 years ago | (#38882795)

Well unfortunately the Broadcom SoC used in this is only available to official Broadcom partners. So no, the typical person who wants to do this CAN'T acquire the parts.

Re:Assumptions (4, Insightful)

Beardo the Bearded (321478) | more than 2 years ago | (#38882223)

If you've got the tools to do it, just buy the pre-assembled system and remove the solder. (Heat-gun soldering stations usually come with a removal gun as well.)

Voila, you've got your kit.

Now put it back together. Now you've done not just one, but TWO difficult, unnecessary things.

I worked with one woman who was a brilliant solderer. Production put a part upside down and she was able to solder it on so it worked. (For firmware development, bought me two weeks of dev time.) It was a QF44 PIC, I was astonished when I saw it.

Re:Assumptions (1)

TheGratefulNet (143330) | more than 2 years ago | (#38882585)

whenver I see a chip upside down, dead-bug style, and wires coming out going to the board below, I grin. I've been there, so I can grin...

Re:Assumptions (1)

Maddog Batty (112434) | more than 2 years ago | (#38882653)

44pin Quad Flat Pack are trivial to remove and replace with the right tools - which basically means a hot air gun with the small nozzle. A couple of weeks ago I removed and replaced two 144 pin quad flat pack devices with 0.6mm pitch legs in about 10 mins. It isn't something I want to do for production boards but it is fine for the development boards I was using.

Screen printing solder using solder masks + ovens are easily within the hobbiest market now. You can get a custom PCB + solder stencil made for £40 (100mm^2) and I use a £50 oven to melt the solder. Gives good results too (though I still do the sub 1mm pitch pins by hand as I get too many shorts otherwise).

I've not attempted BGAs as I could see that the success rate might not be too high.

Re:Assumptions (2)

Anonymous Coward | more than 2 years ago | (#38882737)

We can have competition: how many times you can desolder/solder the yoke before it stops to work?
Extra points if you use only one hand ... and don't tell me what are you are doing with the other one.

Re:Assumptions (2, Funny)

Anonymous Coward | more than 2 years ago | (#38882481)

They might as well include one of these in the deal too, for people who like to do pointless and unnecessary things:

http://www.flickr.com/photos/peterme/3428170/ [flickr.com]

Re:Assumptions (2)

sjames (1099) | more than 2 years ago | (#38882557)

Since it's an open design, the few who REALLY want to do that even though it will cost more than a pre-built unit (due to packaging etc) can probably get together and order the needed parts.

As it is, they appear to be doing a find job getting the pre-assembled form designed and built now, they likely have their hands full.

Re:Assumptions (2)

interval1066 (668936) | more than 2 years ago | (#38882691)

Did you see the illustration in the article? The two main chip packages are pictured on the end of a guy's index finger. Sure, people like to difficult things, but come on! If you're not using the proper ($20,000 +) machine tools you're rate of failure is going to be +/- 90%... just buy the production package, for your own sanity man.

Re:Assumptions (1)

Anonymous Coward | more than 2 years ago | (#38882719)

Tell you what, I'll buy one, desolder all the chips, put it all in a bag and ship it to you for $50. Then you can have fun putting it back together. :)

Re:Assumptions (4, Insightful)

SpaghettiPattern (609814) | more than 2 years ago | (#38882811)

I don't know why people would really want to.

You clearly aren't the target market for a kit form, then.

Seriously, though: the world is full of people who want to do difficult, unnecessary things. It is a human-being feature. All Raspberry Pi has to do is say "Kits are not covered by warranty, period."

In my class I probably was the best at designing PCBs and at soldering and I must disagree with you. Times have changed -and I'm also getting older- and I find it hard to sensibly compete -even as a hobbyist- with mechanical, industrial level soldering, which is what the Raspberry hopefully meets. Also, trying and failing is probably less of a nuisance than trying, nearly succeeding and winding up with weird situations because of soldering issues. Spoke as a tinkerer.

Re:Assumptions (2)

symbolset (646467) | more than 2 years ago | (#38882867)

Everything is sold in kit form. Just packaged in a convenient form for kit testing. Just put it in your toaster oven and the components fall right back apart for your assembly challenge. I've soldered some of these tiny components before. You'll want to lay off the coffee for a few days prior.

Re:Assumptions (3, Insightful)

Austerity Empowers (669817) | more than 2 years ago | (#38882339)

No the assumption is that you don't have the capacity to solder a BGA at home. You don't do this with a soldering iron, you do it in an oven, and you have to place the part precisely enough that it can self orient. I have heard of hobbiests doing this chip-to-pcb with larger pitched BGAs, but not fine pitch, and not chip to chip. I just don't think this is a good use of time or money, considering you will probably break a few.

But if you really want to do it, the gerbers are out there. There are lots of cheap board fabs, use one of them, then just go acquire the parts from digikey.

Re:Assumptions (3, Informative)

queazocotal (915608) | more than 2 years ago | (#38882767)

The chips are not available from digikey, only directly from broadcom, in large numbers.(tens of thousands)

Re:Assumptions (1)

Suki I (1546431) | more than 2 years ago | (#38881917)

I don't like the assumptions they're making.

Ditto! I could mess up soldering a 0 gauge wire to a car battery terminal, but I should be free to do so and waste my own funds doing it!

Re:Assumptions (-1, Flamebait)

Anonymous Coward | more than 2 years ago | (#38882015)

Freedom? Why do the most idiotic Americans always bring up liberty in every goddamn discussion?

Go ahead. Buy one, take it apart and do a worse job putting it back together. Who's stopping you?

If they don't want a bunch of yahoos buying kits, screwing up, and then complaining they deserve a refund for a "bad product", that's their fucking right.

The good folks at R.P. are free to run their charity as they like and to tell you and your moronic ideas to piss off.

Re:Assumptions (0)

Anonymous Coward | more than 2 years ago | (#38882093)

Go ahead. Buy one, take it apart and do a worse job putting it back together. Who's stopping you?

For many neat electronic devices, US law.

Re:Assumptions (4, Interesting)

CanHasDIY (1672858) | more than 2 years ago | (#38882129)

I could mess up soldering a 0 gauge wire to a car battery terminal, but I should be free to do so and waste my own funds doing it!

Their business, their decision. Don't like it? Fine; design, manufacture, and market your own credit card sized PC kit, and/or don't purchase any Raspberry Pi products.

I swear, with all the real oppression going on in today's world, it's astounding the nonsense people come up with to bellyache about in the name of "freedom."

Re:Assumptions (0)

Nimey (114278) | more than 2 years ago | (#38882587)

#firstworldproblems
#whitewhine

Before the trolls and idiots who can't google (-1)

Anonymous Coward | more than 2 years ago | (#38881743)

Re:Before the trolls and idiots who can't google (-1)

Anonymous Coward | more than 2 years ago | (#38881813)

Fuck em. If they don't know then wait for them to ask.

Besides you'll still have fucking idiots who won't bother to read your post before they post their stupid fucking questions.

You have done nothing helpful.

Re:Before the trolls and idiots who can't google (-1)

Anonymous Coward | more than 2 years ago | (#38882331)

Fuck em. If they don't know then wait for them to ask.

Besides you'll still have fucking idiots who won't bother to read your post before they post their stupid fucking questions.

You have done nothing helpful.

And neither have you.

http://lmgtfy.com/?q=lmgtfy [lmgtfy.com]

Just an idea... (5, Funny)

Anonymous Coward | more than 2 years ago | (#38881783)

How about we stop posting a Raspberry Pi story every goddamn blog post and save the talk for oh... I don't know... when the god damn thing actually ships?

I've been throwing my money at the screen for months and NOTHING'S HAPPENING!!!

Re:Just an idea... (5, Funny)

Samantha Wright (1324923) | more than 2 years ago | (#38881819)

Well, we tried that, but we ran out of Apple and Google stories to run during the interim.

Re:Just an idea... (1)

SomePgmr (2021234) | more than 2 years ago | (#38881887)

Fortunately there's always plenty of contentious YRO material for us to bicker over.

Re:Just an idea... (0)

Anonymous Coward | more than 2 years ago | (#38882259)

fuck you it's not contentious!

Re:Just an idea... (5, Funny)

Anonymous Coward | more than 2 years ago | (#38881997)

haven't seen a bitcoin story in a while

Re:Just an idea... (1)

QuantumLeaper (607189) | more than 2 years ago | (#38882215)

Microsoft is always good for a laugh..

Re:Just an idea... (1)

b5bartender (2175066) | more than 2 years ago | (#38882925)

Fret not, there's surely a flood of Facebook IPO stories coming down the pipe as we speak.

Re:Just an idea... (0)

Anonymous Coward | more than 2 years ago | (#38881949)

Agreed, I already subscribe to the Raspberry Pi blog.

anal dildos (-1)

Anonymous Coward | more than 2 years ago | (#38881785)

Can i use these to power some anal vibrators?

Re:anal dildos (1)

Anonymous Coward | more than 2 years ago | (#38881817)

Can i use these to power some anal vibrators?

Well, there was a video of a motor running with the PI. You could build a sex machine with it I guess.

Re:anal dildos (1)

Anonymous Coward | more than 2 years ago | (#38882301)

1. "Raspberry Pi
An ARM GNU/Linux box for $25. "
2. "You could build a sex machine with it I guess."
3. "ARM inside" logo
4. ?

"Most people" would mess this up? (5, Funny)

Lashat (1041424) | more than 2 years ago | (#38881793)

Should read EVERYONE without the nimble fingers of a child, the steady hand of a special forces sniper, and the sharpest soldering iron this side of the sun.

Don't forget (2, Insightful)

nweaver (113078) | more than 2 years ago | (#38881837)

Don't forget the reflow oven, so not only do you need superhuman skills, but you need a specialized tool that effectively nobody has.

Re:Don't forget (1)

Wesley Felter (138342) | more than 2 years ago | (#38881919)

Haven't people been reflowing PS3s and Xboxen in their kitchen ovens? Or does that only work for re-reflowing?

Re:Don't forget (0)

Anonymous Coward | more than 2 years ago | (#38882155)

Tin/Lead solder melts at 370F. Most lead free solder melts around 420F-430F. So yes, you can re-flow boards in a conventional oven. The problem is you probably can not apply the correct amount of solder paste to the pads beforehand. I have a lot of experience soldering small packages and would not even bother attempting a BGA. A bad one would just go right back to the factory.

Re:Don't forget (2)

sjames (1099) | more than 2 years ago | (#38882657)

To some extent, that does only work for re-reflowing where the chip is already well placed and tinned. Even then, you are likely to shorten the life of the components somewhat since you won't have good enough temperature control.

Reflow soldering involves heating the components much hotter than they like to be even when powered off. The heating and cooling times are carefully controlled to keep the stress of that to a minimum while still making reliable connections (usually).

Re:Don't forget (0)

Anonymous Coward | more than 2 years ago | (#38881947)

Who doesn't have a toaster [instructables.com] ?

Re:Don't forget (4, Interesting)

Achra (846023) | more than 2 years ago | (#38881971)

People have been doing BGA in toaster ovens for a while now. I'm not saying I'd try it with stuff this size, but it is doable. http://www.die4laser.com/toaster/index.html [die4laser.com]

Re:Don't forget (1)

Anonymous Coward | more than 2 years ago | (#38882317)

There are no BGA's there. I think the smallest parts shown are only 0805 which are huge. I'm also assuming they aren't going to ship a solder stencil with every kit. The stencil they used there cost almost as much as the fully assembled board.

Re:Don't forget (2)

petscii (318753) | more than 2 years ago | (#38882035)

SMD is actually easier than through hole in my opinion if you factor in the time/cost to to drill 400 holes(called vias) in a through hole pcb and the lack of easy plating of vias at home. Also a lot of components are just not available as anything but SMD.

http://hackaday.com/2012/01/01/a-very-detailed-reflow-oven-build/

That reflow oven works, and was built by a lowly technical college dropout (myself) with great success. You just need to get the data sheet for your solder and set up the various temperatures required for the solder paste to do its thing. You also can't use the toaster oven for pizza afterwards. But it's 80 bucks all in.

Like Ball Bearings, SMD is the future son.

Re:"Most people" would mess this up? (1)

Synerg1y (2169962) | more than 2 years ago | (#38882107)

You can always do stuff to steady your hand temporarily, but I'm not sure where the discussion is: who would want to? Even if you can, the price point might be lower than your hourly wage so why bother. There's plenty of other stuff to solder, like your friend's gaming console :)

BGA packages are intimidating (5, Informative)

vlm (69642) | more than 2 years ago | (#38881829)

BGA packages are intimidating, even to a guy who's been hand soldering other SMD packages since around/before 1990 (that being me)

Plain SMD is easy to do by hand, even the 0402 stuff.

The thing with BGA is its an alignment problem. Some entrepreneur will likely invent a magic clamp that holds the chip in perfect registration to the PCB, at which point it'll be dirt simple to solder BGAs.

I donno where the "if you're a millimeter out, your chips are fried" stuff comes from because thats /.ed. I've done analog microwave RF work where that is actually true. That is not possible on a logic level board. "oh noes, /ce has been grounded, whatever shall we do?" Well just fix the solder bridge and stop whining. Its not like you just shorted out a 20 amp 24 volt power supply thru the bias/bypass network of a microwave FET amplifier, nothings going to blow up on a digital ckt.

Re:BGA packages are intimidating (1)

SomePgmr (2021234) | more than 2 years ago | (#38881923)

I have a hard time with the smd stuff. Probably not enough practice, but even with reasonably steady hands and a magnifying lamp on my workbench, I tend to screw things up. And these things are so cheap to begin with, I'd have bought the assembled model anyways.

Re:BGA packages are intimidating (5, Informative)

allanw (842185) | more than 2 years ago | (#38881951)

I don't understand why people even want a kit at all. The assembled version is already ridiculously cheap due to high volume. There's tons of surface mount parts that would be annoying to even package for people. Why ruin a perfectly good small form factor to make it a little easier for a few people who want to solder it themselves? Also, it would take you hours of your own time assembling it. Why don't people design their own hardware instead?

The much bigger problem is the lack of documentation on accessing the GPU (which is a more modern design and pretty powerful compared to the older ARM CPU core they're using)

Another issue is that it is very hard to debug an assembled board. If one of the pads on the BGA doesn't make contact it's nearly impossible to diagnose. A power to ground short would be very difficult to locate. They can't use their automated test jig to sort out defective parts or errors in assembly, etc. And then the manufacturer will be prompting tons of support requests by people. It really isn't worth the effort.

Re:BGA packages are intimidating (4, Insightful)

TheGratefulNet (143330) | more than 2 years ago | (#38882507)

I want one assembled AND TESTED.

I'll pay for that.

debugging a software bug (my own code, say) is hard enough without second guessing the hardware.

csb: a friend of mine is trying to convince me to use an arduino mega (high density smd-only chip) where I'm currently using the skinnydip28 version of the regular 328-style arduino (which is .1" thruhole and easy to deal with). at the very least, if I was moving to a mega (25xx class), I'd insist on it being on a carrier board AND that board being built to high spec and the cpu tested on the board before being delivered to me for assembly into a larger system. I refuse to have to worry about the cpu AND the rest of the system (being a small company). I cannot find good mega-class chips already on carriers (.1-friendly carriers) AND tested AND by a company I'd trust to actually care about quality. being able to buy it pre-tested is key, to me.

back to r-pi: I'd want this to be known and tested as a FRU of its own. the thing is small enough to be its own field-replaceable-unit in a larger embedded system; and if any part on it is bad, the whole thing gets replaced.

Re:BGA packages are intimidating (1)

vlm (69642) | more than 2 years ago | (#38882935)

csb: a friend of mine is trying to convince me to use an arduino mega (high density smd-only chip) where I'm currently using the skinnydip28 version of the regular 328-style arduino (which is .1" thruhole and easy to deal with). at the very least, if I was moving to a mega (25xx class), I'd insist on it being on a carrier board AND that board being built to high spec and the cpu tested on the board before being delivered to me for assembly into a larger system. I refuse to have to worry about the cpu AND the rest of the system (being a small company). I cannot find good mega-class chips already on carriers (.1-friendly carriers) AND tested AND by a company I'd trust to actually care about quality. being able to buy it pre-tested is key, to me.

I haven't worked w/ that hardware, but can't you do your software work on some dev board, even if you have to really hack the heck out of the dev board with wires laying everywhere? I've certainly done stomach turning things to poor defenseless dev boards in the past. I agree doing hardware and software dev at the same time is ... overly exciting.

I donno if you like or hate seeeed studios or whatever but slapping together a simple single chip carrier PCB and having them solder just one chip to one simple board can't be all that complex for them. I've bought stuff from them that turned out OK. Maybe the killer would be lead (oh, bad pun in a SMD thread) time?

Re:BGA packages are intimidating (5, Interesting)

vlm (69642) | more than 2 years ago | (#38882581)

I don't understand why people even want a raspberry pi at all. The apps on the itunes app store are cheap. Why ruin CS and IT to make it a little easier for people who want to write their own programs? Also it would take you hours of your own time to write and compile your own software.

Come on man, its a hobby. When a dude puts together a 1000 piece puzzle you don't pee all over it by claiming you can buy a poster of the same picture and thats a better choice because you don't have to put it together... That kind of misses the point.

The fun fun fun of kit assembly isn't in working a 16 hour shift assembling it with chinese music on pandora, eating a couple rice grains and some tea while wearing a political prisoner uniform, and pretending your boss beats you for not working hard enough. Unless you like that kind of stuff. Whatever floats your boat. Anyway the fun of kit building is kit bashing weird stuff from different eras to massively customize the project to what you want. Something I've been up to on the bench recently: I started with a fairly modern microwave local oscillator kit. Then I swapped out the crystal because I need to work on a different frequency for a completely different ham radio frequency band. Then I smooshed in a completely different voltage regulator circuit; ugly as heck but I don't care; I want/need to run off 24 volts instead of 12 volts (long story there). Didn't want to buy a modern MMIC amp for the board because I had some old 80s era tech mmics laying around so I redesigned the bias ckt for the correct voltage drop and forward current (exactly as complicated as lighting a LED, just stuck a different value resistor in; didn't wanna build a constant current supply, at least not this time). So far so good. Also added a stylish power LED so I can tell my regulator hasn't shut down from overheating..... yet.

I think it would be fun to completely redo the I/O on a raspberry pi, at least to begin with that is the most obvious thing to do. Also some stuff I simply don't care about, I would not solder on. Not gonna do the composite video thing, not gonna waste time soldering it on. Probably would rip out the audio stuff figure out how to directly wire a software defined radio directly to the board. If the first thing in the TX chain on the SDR is a giant attenuator, and the last thing on the Pi audio out is a high powered headphone amp, simplicate it and toss both replacing both ckt sections with a piece of wire. etc.

Re:BGA packages are intimidating (1)

gknoy (899301) | more than 2 years ago | (#38882849)

Giving your kid a Raspberry Pi, letting him hook in a keyboard and plug it all into the TV, and then get started programming makes it seem pretty compelling. Of course you might not be building large apps and games, but come on -- nearly every toy or educational program one might write will run just fine in an interpreted environment, and would likely compile very quickly.

Being able to run XBMC and hardware accelerated 3d graphics are neat, too, of course.

Re:BGA packages are intimidating (0)

Anonymous Coward | more than 2 years ago | (#38882031)

I donno where the "if you're a millimeter out, your chips are fried" stuff comes from because thats /.ed.

Probably because you've put vcc/gnd on the wrong pin which fried the thing. This is easy to do for hobbiests on far more robush IC and modules. I have no idea why you would even begin to imagine a BGA SoC is somehow so hardy it can easily withstand such abuse. The editor's comments seems to be extremely accurate in spite of your contrary statement.

Re:BGA packages are intimidating (1)

Anonymous Coward | more than 2 years ago | (#38882201)

the alignment isn't really the biggest problem, bga's are to a large extend self aligning as long as you get pretty close the surface tension of the solder will align the chips on its pads

but you'll need a stencil to put solderpaste on the pcb and then a reflow oven to solder those pads, getting all the pads soldered and not melt the chip in the process
is delicate.

with determination and practice sure it is possible to do but there is really no point

Re:BGA packages are intimidating (1)

vlm (69642) | more than 2 years ago | (#38882791)

Yeah my alignment idea is to hold it in place while doing the hot air rework station thing. Agreed, don't need that alignment jig to hold in place for reflow oven, but I've never used a reflow oven, not planning to start any time soon. Supposedly you can rely on surface tension on a vibration free basically immobile horizontal within X degrees where X is pretty small. But I wanna use an alignment jig so I can just flip it onto the desk and use the rework blower (or, maybe, nudge it by hand if I've got vias to all the pads.

soapbox time: Some of the "agony" of SMD seems to come from history... Early leaded factory assembly was done by hand exactly like the dude in the basement; wave soldering and leaded pick and place came decades later so no one freaks. Early SMD factory assembly never had a "done by hand" assembly line, at least outside of aerospace and microwave RF, so people think the only way to do SMD is to own a reflow oven, stencils/paste, and a picnplace... yeah sure just like the only way to put a leaded pcb together is to own a leaded picnplace and a leaded wave soldering machine... hmmm. You wanna learn how to leaded solder, you learn how factories did it 60 years ago. In sharp contrast, don't waste time studying how factories used to do smd, if you want to do it at home... learn how the rework guys do it by hand today, if you want to learn how to do SMD at home. After the rather sharp learning curve, its pretty easy.

Re:BGA packages are intimidating (1)

CaptainLard (1902452) | more than 2 years ago | (#38882783)

nothings going to blow up on a digital ckt.

What if the chips have different I/O and core voltages? This is true for many processors and FPGA's that come in BGA form. I'd bet the ball pitch is .5 or .4mm so if you're off by a mm you could easily connect 3.3V to the 1.2V core. That would indeed fry the chip. Or 3.3V could go straight to ground which could fry the actual PCB since the traces are 5 mils or less and can't handle 500mA for long. Also, that "magic clamp" exists as a $60k CNC heat column in my lab at work. Once you program the reflow profile, the board layout, and the chip pressure it is indeed dirt simple.

Disclaimer: All board stats listed are pure speculation

Re:BGA packages are intimidating (0)

Anonymous Coward | more than 2 years ago | (#38882809)

BGA's with rework gel self-aline pretty well when then hotair is controlled as per the reflow curve, with smaller chips you don't even need the preheat the board.

whatever... (4, Insightful)

spidercoz (947220) | more than 2 years ago | (#38881839)

I still want 10 of them...

Re:whatever... (1)

Anonymous Coward | more than 2 years ago | (#38882061)

Yeah, I want a few too but I have to admit that my interest is starting to wane in a big way. It seems that we get a new gizmo like this about every 9 months that we hear story after story about how cool it is and they either never materialize or we find out that the claims were over the top in respect to the reality of the situation.

Re:whatever... (1)

jcreus (2547928) | more than 2 years ago | (#38882123)

For a price which would be one millionth of the typical Apple product.

Hand-soldering BGA packages is hard (1)

normaldotcom (1521757) | more than 2 years ago | (#38881901)

Correctly soldering BGA packages requires a reflow oven or a good heat gun with some solder paste. This is intimidating not only for customers with basic soldering skills, but even those who have extensive experience soldering other small SMT packages. Nevertheless, releasing the PCB as open hardware would allow people to fabricate and assemble their own boards, without placing an additional burden on the company.

Re:Hand-soldering BGA packages is hard (0)

Anonymous Coward | more than 2 years ago | (#38882205)

Placing additional burden?

The Foundation (not company) turns a profit on every unit. They *want* to produce as many as can be sold! (see forum threads), to increase funds, develop it further, sell more, world domination, etc.

Fix this, MacGyver! (4, Funny)

Chemisor (97276) | more than 2 years ago | (#38881981)

And to think that only 30 years ago a resourceful fellow could fix a circuit board with a silver dollar, pliers, and a car battery. With today's electronics, MacGyver would be dead.

Re:Fix this, MacGyver! (1)

93 Escort Wagon (326346) | more than 2 years ago | (#38882047)

And to think that only 30 years ago a resourceful fellow could fix a circuit board with a silver dollar, pliers, and a car battery. With today's electronics, MacGyver would be dead.

Fortunately Ben Browder would still be available to play his replacement.

Re:Fix this, MacGyver! (1)

Anonymous Coward | more than 2 years ago | (#38882341)

He can't even fix his own car.
http://www.dailymail.co.uk/tvshowbiz/article-2073702/MacGyver-actor-Richard-Dean-Anderson-looks-clueless-car-breaks-down.html

Re:Fix this, MacGyver! (0)

Anonymous Coward | more than 2 years ago | (#38882359)

A 2012 MacGyver would just "hack the firewall".

Re:Fix this, MacGyver! (2)

TheGratefulNet (143330) | more than 2 years ago | (#38882549)

serious answer: you 'fix' this by having shelf spares.

when one breaks, you replace it. maybe send the bad guy back but definitely swap it and you need to have spares on the shelf.

Re:Fix this, MacGyver! (3, Interesting)

gman003 (1693318) | more than 2 years ago | (#38882567)

With today's electronics, MacGyver would just do it all in software.

Re:Fix this, MacGyver! (1)

CaptainLard (1902452) | more than 2 years ago | (#38882889)

Not if he had Jack Bauer's writers:

Terrorist: Fred, Rewire the CI-Plot Device to blow up the eastern sea board or I'll tell Suzie you cheated on her!

...6 min later...

Fred: Jack! the terrorist just escaped via submarine helicopter!

Jack: Chloe, patch me through to the Deap Sea satellite imaging array!

Import/Export Tax (3, Informative)

Anonymous Coward | more than 2 years ago | (#38882063)

I thought the main reason they couldn't build the Raspberry Pi in the UK was there were prohibitive costs to importing the needed components whereas the completed device was taxed differently.

Isn't this the same problem?

Enough about this board (4, Insightful)

Animats (122034) | more than 2 years ago | (#38882079)

The stories about this board need to stop, at least until they ship the thing. "We bought the parts". "We soldered them on", etc. do not each need a separate story.

Of course you don't ship kits of SMD parts, especially ball-grid array parts. Such a soldering job is cheap in a production environment, and a huge pain even with the right equipment in a small shop. (It's done in production by printing a solder paste layer on the board with a mask, and the final alignment of the pads is done by surface tension in the molten solder. It's all about temperature control and solder paste depositing. Once the production line is tuned right, it works quite consistently.)

Re:Enough about this board (0)

Anonymous Coward | more than 2 years ago | (#38882757)

I think the Raspberry Pi Foundation would agree with you there.

Each time an enthusiast submits a story, damn Slashdot runs it and the Raspberry Pi site gets swamped by numbskulls popping over to see what the fuss is about. Believe me, the folks in charge have better things to do than submit teaser stories here.

As for all this business about "kits", someone, a long time ago, took it into their head that the Raspberry Pi was going to be shipped as a kit and its become one of those damn internet memes. Bunch of effin lunatics with too much time on their hands, if you ask me.

News isn't the soldering, but the OSS libraries (4, Interesting)

AceJohnny (253840) | more than 2 years ago | (#38882137)

The fact that they won't deliver in kit isn't news*, it's more interesting to know that they have HW-accelerated versions of MPEG4 and H.264 (and only those), and that all these libraries are closed source.

Furthermore, claims that they have the fastest mobile GPU are fluff: we only have the subjective word of someone who worked on it, not a neutral 3rd party, and it'll be caught up by someone else soon anyhow.

Finally, I'm going to advance that any complaints about the nvidia binary driver are going to be small fry compared to Broadcom's drivers.

*it's just not possible to hand-solder BGA packages. At best you'd need a reflow oven, and *that's* still tricky with the sizes involved here.

Re:News isn't the soldering, but the OSS libraries (0)

Anonymous Coward | more than 2 years ago | (#38882385)

Yeah, also I have serious qualms about this being a Broadcom platform. It really needs to be more open, can't have a big binary blob in the middle of the thing. Of course, with enough minds, reverse engineering is a possibility, but I doubt Broadcom would respond kindly to that.

Re:News isn't the soldering, but the OSS libraries (2)

fuzzyfuzzyfungus (1223518) | more than 2 years ago | (#38882583)

Inconveniently, SoC GPUs that aren't driven by huge binary blobs appear to be pretty thin on the ground. It makes the PC scene look like a haven of pure openness(in that you can get intel stuff if you don't care much about performance, the AMD stuff will be here one of these days, and nouveau sometimes works on the right Nvidia chips...)

With BCM certainly doesn't have an overly cooperative history; but PowerVR, ARM's own Mali, and the not terribly long list of others are not exactly more helpful when it comes to mobile GPUs.

Worthless as a media streaming device (2)

JDG1980 (2438906) | more than 2 years ago | (#38882245)

This article also confirms that the Raspberry Pi will likely be worthless as a media streaming device - at least for those of us who care about video quality.

It is now official that only H.264 (and MPEG-4) will be supported for hardware decoding. That means that playback of ripped Blu-rays that use VC-1 and MPEG-2 (not an inconsiderable number) is impossible, since the weak ARM CPU will almost certainly not be able to decode them in real-time at 1080p.

I'm sure the Pi will work fine for people who play back transcoded crap downloaded from TPB, but for anyone who actually cares about video quality, the lack of these essential codecs is a death sentence. We can only hope that at some point in the future a different (even if more expensive) model will ship with them enabled.

It's really a shame that there is currently no open-source-friendly SoC platform that supports HD video decoding and HDMI 1.3 audio bitstreaming in all its forms. HTPCs mess with the signal in all kinds of ways (YUV->RGB conversion is forced, even if you select YUV, it converts to RGB then converts back) so SoCs are really all that can provide decent quality. And the firmware on commercial media streamers is almost all crap.

Re:Worthless as a media streaming device (5, Insightful)

Anonymous Coward | more than 2 years ago | (#38882311)

So you're saying if you care about video quality you should spend more than $25?

Re:Worthless as a media streaming device (4, Informative)

Hatta (162192) | more than 2 years ago | (#38882471)

HTPCs mess with the signal in all kinds of ways (YUV->RGB conversion is forced, even if you select YUV, it converts to RGB then converts back)

RGB to YUV is lossless in both directions.

Re:Worthless as a media streaming device (4, Funny)

Anonymous Coward | more than 2 years ago | (#38882625)

HTPCs mess with the signal in all kinds of ways (YUV->RGB conversion is forced, even if you select YUV, it converts to RGB then converts back)

RGB to YUV is lossless in both directions.

But you lose the overtones.

Re:Worthless as a media streaming device (1)

Anonymous Coward | more than 2 years ago | (#38882629)

RGB YUV is only lossless in analog. Once you have to round the result to 8-bit, it is lossy.

Re:Worthless as a media streaming device (0)

Anonymous Coward | more than 2 years ago | (#38882521)

SoC platforms for video decoding are always crap. Work alright for 60% of files, not too badly for another 20%, and either fail or suck hardcore for the last 20%. VC-1 shares a lot of features of H264, so it might unofficially accelerate VC-1.

Re:Worthless as a media streaming device (1)

Svartalf (2997) | more than 2 years ago | (#38882981)

Depends on the profile more than anything else. And it's not hardware in the normal sense for most of them- they're using a DSP based codec.

Re:Worthless as a media streaming device (1)

Microlith (54737) | more than 2 years ago | (#38882651)

I'm sure the Pi will work fine for people who play back transcoded crap downloaded from TPB, but for anyone who actually cares about video quality, the lack of these essential codecs is a death sentence.

That's fine. The Raspberry Pi isn't really even intended for use as a media streaming device. Considering how much the h.264 license probably cost, I can imagine they happily put the other codec license fees on the back burner to retain the target price of the platform.

It's really a shame that there is currently no open-source-friendly SoC platform that supports HD video decoding and HDMI 1.3 audio bitstreaming in all its forms.

Trade secrets and software patents are the name of the game in the mobile SoC space.

HTPCs mess with the signal in all kinds of ways

Being an HTPC, you would be able to configure this? I'm confused as to why an undesired conversion would take place, given that HTPCs tend to be custom built by the user.

Re:Worthless as a media streaming device (0)

Anonymous Coward | more than 2 years ago | (#38882773)

Odd you discount H264 over MPEG-2 and VC-1. MPEG2 is inferior quality than H264 at the same bit rate, VC-1 is about the same. Rip your whatever at a high enough bitrate to H264 (and the SoC support Bluray bitrates, which uses H264 or VC-1) and you will have no quality problems. Certainly better than MPEG2.

MPEG2 is also a very expensive license ($2/device) compared with H264. That's nearly 10% of the cost of the Model A.

Ever wondered why there are no open source friendly SoC's that do this? Because SoC and the software on them cost a lot to develop, and all the manufacturers who make them need to get the dev costs back. It's a very competitive market.

Re:Worthless as a media streaming device (0)

Anonymous Coward | more than 2 years ago | (#38882957)

That means that playback of ripped Blu-rays that use VC-1 and MPEG-2 (not an inconsiderable number) is impossible, since the weak ARM CPU will almost certainly not be able to decode them in real-time at 1080p.

You DO realise that Blu-ray's are encoded in h.264 High-profile, right? Transcoding them down to VC-1 and MPEG-2 doesn't gain anything but size and artifacts along the same lines as the ones you allude to going the other direction... If it was to play on hardware that's not capable of doing MPEG4/h.264, I might be willing to give you a pass. But if that's not the case...heh...better not own up to it because you just made yourself look beyond foolish there.

In either case, I find that it'll be hard to get anyone to be concerned or believe your position on media streaming.

The response from the RPi forum (5, Interesting)

AdamHaun (43173) | more than 2 years ago | (#38882485)

http://www.raspberrypi.org/archives/592#comment-10077 [raspberrypi.org]

liz on January 31, 2012 at 9:17 pm said:
Indeed – we have to use an x-ray machine with microscopy to ensure all the pads are connected properly. And NOBODY has one of those at home.

This post has just been Slashdotted. http://hardware.slashdot.org/story/12/01/31/203229/why-the-raspberry-pi-wont-ship-in-kit-form [slashdot.org] Plenty of commenters there appear downright insulted that we don’t think they’ve got ovens, masks, and an x-ray machine at home, along with the dexterity of a TINY TINY PIXIE. (They don’t have any of those things, but they’re still insulted.) Sometimes I really hate Slashdot.

Re:The response from the RPi forum (1)

locallyunscene (1000523) | more than 2 years ago | (#38882787)

Well played.

Why are we talking about the Pi seriously? (0)

Rogerborg (306625) | more than 2 years ago | (#38882861)

They have a limited initial run of devices, half of which will be defective in some way, and the returns will kill them off before they ever get a chance to ship in volume. 3 months and we'll be reading about how it all went wrong, and the lessons they learned.
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