USB discussions getting a bit heated

Morgaine Dinova wrote:

 

The Pi is in reality not a general purpose computer.  It's half a computer, with the ARM being used to fill in the hardware gaps that let the SoC be designed at the lowest possible cost.  If you try to use the ARM at the same time for normal computing, you can kiss your SoC's correct functioning goodbye.

The BCM2835 is a powerful media processor with a cheap ARM11 hanging off the side as an I/O processor to take care of housekeeping tasks like USB.  We're allowed to use the housekeeping processor for pretty much anything we want, and it's a pretty nice little GNU/Linux processor.  It's sure a lot more powerful than the PDP-11/45 I first used for Unix   We have limited access to the media processor, i.e., we've been given a book of spells and we're allowed to invoke those spells but have no idea what magic makes the spells work.

RasPi does meet its requirements for being a good platform for learning about programming.  Kudos.  RasPi is cheap enough that you can play without worrying about breaking the family PC, and it's a very responsive platform for compiling and running reasonably sized programs.  It can also be a nice little platform for some embedded projects, such as the Pi in the Sky.

I like to compare RasPi to a supercomputer.  It has a powerful supercomputing engine, but we're only allowed free access to the I/O processor.  It's disappointing for people who see that RasPi could so easily be so much more if they would just release documentation, but sometimes life is like that.  There are plenty of alternatives for people who want a more open system.

John Beetem wrote:

 

We're allowed to use the housekeeping processor for pretty much anything we want, and it's a pretty nice little GNU/Linux processor.

We're allowed to use it, sure.  The trouble is that when we do start to use it, the SoC's housekeeping is compromised and perfectly normal computer operations (like receiving USB events) start failing.

The ARM core is working perfectly, but that's not the whole computer.  Add in the I/O systems and it is no longer working perfectly.

John Beetem wrote:

RasPi does meet its requirements for being a good platform for learning about programming.  Kudos.  RasPi is cheap enough that you can play without worrying about breaking the family PC, and it's a very responsive platform for compiling and running reasonably sized programs.  It can also be a nice little platform for some embedded projects, such as the Pi in the Sky.

If everything worked as it should, it would be ideal for everything you mentioned. However if one can't rely on it to function reliably, then instead of worrying about breaking the PC, one has to worry about having the right setup to get the Pi to work.

Morgaine wrote:

 

It should be pointed out that this isn't a case of the community being over-demanding, and the complaints aren't coming from people intent on destructive stress testing.  They come from ordinary users who are expecting (shock horror!) that when they attach a common USB device and it is recognized by an available driver, that it should then work.

+1

It should be pointed out that this isn't a case of the community being over-demanding, and the complaints aren't coming from people intent on destructive stress testing.  They come from ordinary users who are expecting (shock horror!) that when they attach a common USB device and it is recognized by an available driver, that it should then work.

and as any decent engineer knows, best way to test your device is to put it into the hands of those ordinary users.. Agreed that they're not deliberately going to do destructive stress testing, but often that's the result as they'll think of things to do with it and ways to use it that you didn't think of and never designed it to cope with.  Most stuff indended for consumer hands would go through many iterations of that before a general release. The Pi didn't, it has some issues. Surprise !

over-demanding ?  expecting random, even if common, untested devices to work ?  IMHO maybe some people are expecting too much, it's easy enough to find a common usb device where the manufacturer provides zero linux/mac support as he designed it for windows and there's either no community linux driver or a very poor one. Funnily enough those are usually usb wifi adaptors (or synopsis usb otg controllers)

I think it would be interesting to see what would happen if all the Pi were recalled, to be replaced with an OlinuXino or Beagleboard. Would either of them fare differently in the hands of 300K+ ordinary users ?  I'm sure the issues would be different, but equally sure that someone would be complaining about something.

Hopefully if there ever is a Pi-v2.0 some lessons will have been learned from this time round on all sides. Not holding my breath on that one

selsinork wrote:

 

over-demanding ?  expecting random, even if common, untested devices to work ?

Yes, fully expected to work, if they're class-compliant USB devices.  That's why we have standards in this business, so that you don't have to test each device individually with each different brand of computer.

Morgaine Dinova wrote:

 

It should be pointed out that this isn't a case of the community being over-demanding, and the complaints aren't coming from people intent on destructive stress testing.  They come from ordinary users who are expecting (shock horror!) that when they attach a common USB device and it is recognized by an available driver, that it should then work.

JMO/YMMV: As far as I know, this is still the developer version of RasPi, so anyone who buys a RasPi should realize they're participating in a beta test and that problems will most likely occur (and recur due to regression) and they should help the community by reporting problems and work-arounds.  Part of the fun, n'est-ce pas?

From the forum comments at raspberrypi.org, it's clear that lots of people bought a RasPi without realizing it's a beta product.  I think it's fair to criticize the RasPowersThatBe for not having been more energetic about making this clear, but it can be hard to get the tech media to report tech accurately.  If they've got more than 50% right, you're in great shape.  The RasPTB may have just figured that "hey, we told you so, how can you imagine that an uncased board with no power supply could be anything other than beta?"

I would hope the USB issues get ironed out in time.  We'll see.  Maybe they'll end up with permanent beta software.

JMO/YMMV

selsinork wrote:

 

I think it would be interesting to see what would happen if all the Pi were recalled, to be replaced with an OlinuXino or Beagleboard. Would either of them fare differently in the hands of 300K+ ordinary users ?  I'm sure the issues would be different, but equally sure that someone would be complaining about something.

 

Hopefully if there ever is a Pi-v2.0 some lessons will have been learned from this time round on all sides. Not holding my breath on that one

I don't have any experience with OlinuXino, but BeagleBoard would probably fare OK.  The hardware is now very stable, having gone through many improvements including bringing out the LCD control pins so you can use VGA or an LCD panel.  The early problems with OTG and the serial port were solved long ago, and there's a good wiki.  OTOH, I'm not sure how easy it is to downloads an OS.  Finding a blessed version of a RasPi OS is easy, and downloading it is straightforward.  BeagleBoard wasn't anywhere as easy the last time I looked into this.  I'd be happy to hear other opinions.

Regarding Pi-v2.0, I don't think the RasPowersThatBe are in any hurry to go through compliance testing again.  It takes a special kind of person to be willing to deal with that chore.

Wait for the A13 new one that is about to become available in September.

-J

After reading the interview on the last MagPi, I find now more difficult to understand what is the mission and the goal of RPF's besides being a self promotion for the Upton's, and a tax free shelter.

Claiming all the time "we are a charity", or "I'm the only full time employee" is 100% BS.

I was really surprised that they are not going to do anything related to produce educational materials.

They clearly demonstrated that can not manage and deliver on such a relatively complex endeavour as producing the R-pi board, their own arrogance transmitted to the clueless minions managing the blog and forum is awful.

Plus the lack of any system to seriously track and analyse problems, the lack of a decent knowledge base, compounded by the blindness that like it or not "sh1t happens."

I totally lost my confidence on anything coming out of RPF, I'm really sad because some of the people at Cambridge are good engineers and have a very interesting vision, but it seems that they no longer have much of a say against the Queen-of-Pi.

I already decided that I'll NOT recommend any of the local schools to get into this nightmare.

-J

It's experiences such as I've just described in a new thread about RF mice used with self-powered hubs that provide a perfect example of the Pi being a complete dog rather than a properly behaving computer.

This is so far from normal in the industry that engineers who aren't affected by the "Pi aura" must be staring in disbelief at what is going on here.  Any normal product exhibiting these faults would be withdrawn immediately from sale and existing units recalled, because it's pretty close to being a non-working product.

And yes, it is a PRODUCT, not a prototype --- people are paying for it, and therefore it is a commercial product by definition.  What's more, the BIS defined it as a consumer product in the UK when they explained why it required certification.

Of course the Pi hype won't permit normal engineering practice to be followed, because there would be too much egg on people's faces and too many plans spoiled.  It's too late, we will have to live with it.  But that doesn't mean that as engineers we should pretend that all is well or as expected.  It's not.  The Pi is faulty.

Morgaine.