Interesting "Competitors" for the Raspberry Pi

The parallela sounds and looks cool but we are talking about a major project that includes sillicon rebake and that probably is 6-12months away from mass production.

Meanwhile while there are other developments that are not exactly comparable to the R-Pi, they are slowly but steady making progress, like the OLinuXino boards from Olimex. I'm testing both the micro and maxi using the Freescale iMX233 application processor SoC (fully documented by the way,) waiting for the A13 one and they also have under development one using the A10. The iMX233 Maxi uses also the LAN9512 and I didn't find any issues with it yet (and BTW the connectors are properly aligned and it has a nice swtiching power supply, the board is slightly bigger than the R-pi, no HDMI/VGA tough.)

I also recently got a TI AM335x Starter Kit, you will start to see more stuff based on the AM335x and TI will get more agressive to dettach the OMAP from some applications and put it on boards similar to the R-Pi.

Still the R-pi continues to be a good idea, unfortunatelly with an associated plan badly executed and with more focus on hype and promotion than really make it a strong and solid "product" with the participation of a community that is eager and able to contribute.

No schematics, no Gerbers, major concern is "cloning" .... I'd not clone something that is not working properly ...

-J

At least it looks like Olimex is taking the problems from people using their boards seriously.

Their Forum is an example of what a forum should be like.

The supply dip when you connect an usb device is a known fact. It might be hard to notice it on a scope, unless you have a good memory scope and are able to trigger it properly. The issue happens more frequently on the newer boards with the usb polyfuses removed. If you look at the Pi schematics, there aren't much buffer capacitors on the 5V supply rail. (just 1 small capacitor). I guess we get what we payed for.

It looks like a lot of the Pi usb issues are caused by timing.

As linux isn't a real time OS, and as stated before that the cpu can become heavy loaded, I doubt they will ever be able to fully fix the issue.

Besides the usb, there are other dissapointing things. One mentionned already is the fact that X11 isn't hardware accelerated.

Another one is the poor quality of the analog audio output. A third one is the fact that you need to properly shutdown the system to avoid sd card corruption. This makes it difficult to use the Pi as an embedded solution. A fourth one is the critical power requirement of the board.

Some of those can be resolved, but all solutions make your cheap solution (not so cheap) anymore.

I know it's a little off topic, but these points are worth checking when seeking for "Competitors" and might rectify a higher price.

selsinork wrote:

 

Not exactly the same, but that's effectively what that Rhombus-tech EOMA thing is trying to do, and as far as I can tell we'll all be old and grey by the time it goes on sale.

Very good point.  I'd forgotten about them, because as you say, the (visible) rate of progress seemed near zero.

There are even places doing exactly what you describe - producing a module with all the bga stuff on it. One I found recently http://bluetechnix.at/rainbow2006/site/i_mx_family/__core_modules/i-mx31-/387/i-mx31-.aspx but go check out the prices and you see why they don't gain the momentum to challenge the Pi either.

Two outfits that love making breakout boards (judging by the high rate at which they release them) are Adafruit and Sparkfun, and instead of price gouging they seem to have a business policy of extremely reasonable pricing.  I wonder if they'd be interested in the concept.

And their respective heads are more than open and willing to be spoken to about ideas, which is wonderful.

@Morgaine I agree, Adafruit and Sparkfun (and maybe Pololu) have done well. I think Limor might be more advanced and open to this idea and with the amount of exposure she draws could really help. She is heavily invloved the RPi though so to a certain extent this might be seen somewhat as a conflict of interest.

Right now we don't have anything to propose. Should we form a group that investigates and creates a solution? Mounting the main processor on a plug in board could be a good way to go to gain more overall support but understand that this adds to the cost and trying to "compete" with RPi the first thing looked at is going to be cost. I think if you're able to come in at around a $50 mark you could generate a lot of interest. Like I said before, I am more than willing to help in more ways than one. There are already quite a few projects on Kickstarter that are nothing more than different modules, and they are getting quite a bit of attention. If something like this evolved and was ready to launch, a Kickstarter project could be a good way to help get it going and my tag line would be that money is needed for HDMI licensing, FCC testing, etc. All those big ticket up front costs that many people don't seem to factor into the bottom line.

I think if you're able to come in at around a $50 mark you could generate a lot of interest.

http://cubieboard.org/ supposedly going to be $49 plus shipping etc. So that's your competition. 

Realistically, today, an A10 board of some description is probably the best all-round SoC to base a design on. Notice that Olimex, CubieBoard, Rhombus-Tech and others are all choosing it.

Also as it uses the off-the-shelf from Arm  Mali GPU and there's already an effort to produce OSS drivers it's likely to be a better bet than the bcm2835 GPU. It doesn't matter that it's slower than the broadcom device as there's no drivers for the broadcom anyway..

selsinork wrote:

 

Realistically, today, an A10 board of some description is probably the best all-round SoC to base a design on. Notice that Olimex, CubieBoard, Rhombus-Tech and others are all choosing it.

I think that an important part of doing something interesting and open in this area would be to harness some of these companies, instead of competing with them.  If they can provide parts of the puzzle and the concept enhances their business instead of competing with it, this builds buy-in to the idea.  It can even create synergy with their existing product lines and bring an ecosystem into being, as happened with Arduino and shield suppliers.

For example, Olimex offers to sell A13+PMIC pairs for those who want to clone their new A13-based boards.  With that kind of remarkably open attitude, they would probably also be willing to be involved in an open enthusiast project such as we're discussing, because they could manufacture industrial range versions of it.  And of course, they are very much in the business of making small volume industrial and enthusiast boards with very tight profit margins already.

Adafruit are undoubtedly annoyed at not being a primary supplier of Raspberry Pi because of RPF's manufacturing and distribution cartel, so it wouldn't surprise me at all if they would be interested in a plan do something similar using a more open SoC and an open hardware design that they could manufacture.

Morgaine.

The CubieBoard is interesting and I would have to think that it's the closest competitor to the RPi at the moment. To be honest though, I get nervous with products that are produced in China. I have had some boards built there and I also procure some parts from there BUT on MANY occasions they have been known to change components at will and I'd bet that is a primary reason for the recent move of the RPi manufacturing.

@Morgaine, maybe you're right and Adfruit would be interested in something like this or maybe the CubieBoard will evolve at a more rapid rate. For me the longest part of the product bringup after the design has been finalized is the testing and approval of the prototypes. Once that's done it should just be a matter of ramping up production at a controlled rate.

I guess I'll shoot an email to Limor and see if she's interested...

Jonathan Garrish wrote:

 

1) The hardware: ARM - not so much a platform as a sprawl. It's overwhelmingly used to power consumer devices, so maturity, backward compatibility, future security and all the other stuff that a community needs to get a piece of hardware to do something interesting just isn't there. Your chosen software may not even have an ARM port. Obviously this is no barrier for the dedicated geek with access to source code, but it's a faff. The fact that ARM is such a mess certainly doesn't encourage software developers to embrace it...

 

2) The software: ... but as ARM is so splintered I really don't see the situation changing any time soon for consumers who want an ARM P.C. for general duties and want it to work out of the box without having to constantly *** around in terminal.

ARM has an interesting history.  As I recall it, the previous time ARM had a presence in general-purpose computing was with the Acorn, back when ARM stood for Acorn RISC Machine and the ARM2 processor was indeed RISC.  Then they made it big in the Apple Newton, which I don't think of as a general-purpose computer.  At this point they became Advanced RISC Machines, reflecting advances (and increased complexity) in the architecture.  They had a corporate mind-set of low power consumption, so when a 32-bit processor was needed for cell phones ARM was the obvious choice.  Again, we're talking embedded applications, not general-purpose computers.

In embedded applications you're running built-in software, so the problems with multiple versions of ARM aren't so serious.  You know what version of ARM the product has, and you can compile and optimize for that architecture.  Since every one of your 1 million users are going to be running that same software, it's worth buying the best ARM compiler you can and worth spending the time to use performance-tuning software to find the bottlenecks and rewrite them in ASM.  I've heard that GCC does a poor job with ARM architecture by not making effective use of conditional execution of instructions.  Instead it uses conditional branches, which can destroy performance in a processor with long pipelines.

Now we're seeing ARM once again being used as a general-purpose computer, using inexpensive compilers that probably haven't been tuned for it.  However, with 0.5 million RasPis out there and 1.0 million estimated for the first year of sales, there's finally an incentive to get in there and make decent ARM code generators.  So I don't see compiling for ARM as a long-term problem.

ARM has a huge for a laptop application: very low power consumption so long battery life.  I've never bought an x86 laptop because IMO it's silly to use a laptop that warms your lap, or worse, needs a fan pad.  I just put together my first laptop: a RasPi with Atrix Lapdock   ARMs are fast enough for decent laptop/desktop performance, as long as they have enough memory for your target applications and decent mass storage performance.  The software will catch up.

Morgaine Dinova wrote:

 

George, it's no different to hobbiest suppliers often providing a semi-populated board containing only the SMT components for the design already placed, in order to support those enthusiasts who like to construct but for whom soldering SMT is difficult.  There are many such people, even today with the wide presence of SMT.

 

Likewise, soldering BGA would be problematic for the majority of hardware enthusiasts, so providing the BGA part on a plugin module would play a similar role.  The rest of the board would be constructable by the majority of enthusiasts using their more common building skills, which does not include handling BGA.

I don't mind SMT, as long as lead pitch isn't below 1 mm.  I really like the EOMA-68 form factor, which uses a PCMCIA 68-pin connector.  Then you design and build a base board with your custom thingummies, and plug in the EOMA module to provide computing.  Next year, you plug in the next generation module with twice the computing, keeping your base board.

I like SODIMM connectors except for the fine pitch, because they have reliable high-pressure contacts.  I might be convinced to use an SODIMM-144 connector (0.8 mm pitch), but fuggeddabout an SODIMM-200 with 0.6 mm pitch.

John Beetem wrote:

 

I like SODIMM connectors except for the fine pitch, because they have reliable high-pressure contacts.  I might be convinced to use an SODIMM-144 connector (0.8 mm pitch), but fuggeddabout an SODIMM-200 with 0.6 mm pitch.

There are already a few companies using the SO-DIMM-200 and it's mainly used because you almost need all of those pins to get all of the signals out off of the processor. They aren't that bad to solder because most of them have mounting feet which lock there posistion down on the board and then you only need to add solder. But if "we" went this route, wouldn't you want to provide a low cost baseboard that brings all the signals out anyways? If you're trying to reach economy of scale, what percentage of people are really going to care that they might not be able to solder their own connector? Did millions of people not buy the RPi because they couldn't solder the parts themselves? Or for that matter, how many people are even building their own Arduino boards even though you could? If you price a board at ~$50 I don't think too many people are going to go, oh, that's too much, I could solder those parts down and save $5. Look at what TI has done with their launchpad boards, how can you beat a $5 development board? Let people buy the base and fiddle with their own stuff.

George Ioakimedes wrote:

 

John Beetem wrote:

 

I like SODIMM connectors except for the fine pitch, because they have reliable high-pressure contacts.  I might be convinced to use an SODIMM-144 connector (0.8 mm pitch), but fuggeddabout an SODIMM-200 with 0.6 mm pitch.

 

There are already a few companies using the SO-DIMM-200 and it's mainly used because you almost need all of those pins to get all of the signals out off of the processor. They aren't that bad to solder because most of them have mounting feet which lock there posistion down on the board and then you only need to add solder. But if "we" went this route, wouldn't you want to provide a low cost baseboard that brings all the signals out anyways? If you're trying to reach economy of scale, what percentage of people are really going to care that they might not be able to solder their own connector? Did millions of people not buy the RPi because they couldn't solder the parts themselves? Or for that matter, how many people are even building their own Arduino boards even though you could? If you price a board at ~$50 I don't think too many people are going to go, oh, that's too much, I could solder those parts down and save $5. Look at what TI has done with their launchpad boards, how can you beat a $5 development board? Let people buy the base and fiddle with their own stuff.

I'm not interested in soldering to save money.  That concept went away a few years before Heathkit went out of business.  The reason I'm interested in 1mm+ pitch is so I can create custom baseboards with specialized interfaces and assemble them myself, and then plug in a module that has all the fine pitch and BGA components, such as Variscite SODIMM-200 or Gumstix.  However, both of those require fine-pitch connectors.  Now, it may be that in addition to low-cost PCBs you can find places that will also solder down a few fine-pitch components as well.  Unless such exist, I either need 1mm+ pins or I'll just buy a BeagleBone or Cubieboard or ST Discovery or whatever and make the case tall enough to fit it.

John Beetem wrote:

 

I really like the EOMA-68 form factor, which uses a PCMCIA 68-pin connector.  Then you design and build a base board with your custom thingummies, and plug in the EOMA module to provide computing.  Next year, you plug in the next generation module with twice the computing, keeping your base board.

Me too.  What's more, it's very appealing for making clusters, since such a large number of vertically-oriented EOMA-68 modules can be placed side by aside in a horizontal rack.

This is the age of multicore, allegedly.  We should not be building general purpose computers of any ilk with single CPUs anymore, it will count against our karma at the pearly gates.

John Beetem wrote:

 

I really like the EOMA-68 form factor, which uses a PCMCIA 68-pin connector.  Then you design and build a base board with your custom thingummies, and plug in the EOMA module to provide computing.  Next year, you plug in the next generation module with twice the computing, keeping your base board.

Me too.  What's more, it's very appealing for making clusters, since such a large number of vertically-oriented EOMA-68 modules can be placed side by aside in a horizontal rack.

This is the age of multicore, allegedly.  We should not be building general purpose computers of any ilk with single CPUs anymore, it will count against our karma at the pearly gates.

Morgaine Dinova wrote:

 

Me too.  What's more, it's very appealing for making clusters, since such a large number of vertically-oriented EOMA-68 modules can be placed side by aside in a horizontal rack.

 

This is the age of multicore, allegedly.  We should not be building general purpose computers of any ilk with single CPUs anymore, it will count against our karma at the pearly gates.

Yes, a EOMA-68 cluster sounds great!  It would look something like the inside of the HAL-9000 in 2001: A Space Odyssey

The lesson of multicore: if RasPi had a multicore SoC, one core could handle USB properly and one could run X server full time, eliminating two serious performance issues.

I totally agree with a multicore processor but I fail to see how you think 68 pins is near enough. If we're considering the embedded space then you can't ignore direct connection to an LCD which means 24 pins just for RGB, then there's Ethernet, USB, SPI, PWM, and on and on. You guys were complaining about wanting an easy method to solder devices but it's specialized equipment to weld those PCMCIA clam shells together.

George Ioakimedes wrote:

 

I totally agree with a multicore processor but I fail to see how you think 68 pins is near enough. If we're considering the embedded space then you can't ignore direct connection to an LCD which means 24 pins just for RGB, then there's Ethernet, USB, SPI, PWM, and on and on. You guys were complaining about wanting an easy method to solder devices but it's specialized equipment to weld those PCMCIA clam shells together.

The pincount on a processor module within a multiprocessing cluster isn't really related to all those things you mention, for a variety of interrelated reasons:

• Memory should be local to each processor module because global memory doesn't scale beyond very small processor numbers.
• I/O isn't done on processor modules because all processors need to access it symmetrically without bothering other processors.
• Realtime I/O should be handled by dedicated microcontrollers, not by a  *nix kernel which is very bad at it.
• Microcontrollers provide large numbers of GPIOs and are dirt cheap, so microcontroller-based I/O modules should do all the I/O.
• Communication between processor modules and I/O modules is best done as high-speed serial messaging.
• Serial message communication doesn't need a lot of pins and is topologically very flexible.  Remember the transputer.

I suspect we have completely different designs in mind and hence we are talking about different things.

Morgaine.

I agree that memory should be local but not just to be able to scale, but for timing and pcb layout considerations at high speed data rates. PoP is a good solution because you get rid of all the pcb layout issues but it limits the options for SoC and memory.

Not exactly this (much less their price) but I like this concept:

http://www.teamfdi.com/development-tools-kits/products/6/SOMDIMM-LPC2478

-J

I don't like hand-soldering below 1mm on a regular basis, but it is possible to do 0.5mm and possibly smaller just with a conventional iron, so maybe higher-density connectors are possible if needed. But there are some high-speed serial interfaces for comms, even gigEth ; )  I (like many people I guess) use the solder-wick method (i.e. just solder conventionally with a normal iron and solder, but just have lots of flux on the board first. Then, suck up the bridges with the solder-wick wire. However, most processors are BGA of course : ( This was 0.5mm pitch with a normal antex iron (with a larger bit than I should have really used).

QFN-68 0.4mm pitch, hand soldered

-J

Hehe yes QFN is certainly a skill!

Hey Everyone, I just saw this, http://wandboard.org, at first glance it's looking pretty good but I haven't read the details...

Looks interesting, the iMX6 series of SoC holds promise. I continually wonder about the compromises though - why do I have to buy useless (to me) wifi and bluetooth in order to get dual core and 1Gb ram ?

I see from their google group that someone has already asked the 'accelerated X ?' question, I wonder if he has an RPi

So $69, but what isn't really clear is whether that includes the 'interface board' or if the interface board is a seperate $150 item.

Also at 314 pins I expect the unspecified 'EDM' connector is going to be fairly fine pitch.

The iMX6 will be quite an interesting series of SoC, among other things integrated 1Gbps Ethernet and 3Gbps SATA, etc.

Expect other boards starting to pop up here and there.

-J