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.

Earlier in this thread I mentioned that if you're intending to create an open board, it is helpful if you can encourage an ecosystem to develop around it so that the concept doesn't wither and die through disinterest, and that one way of achieving this is by riding on the backs of existing open hardware companies so that you are broadening the audience for their product lines.  They often like that, and it may even result in some direct support for your cause.

I mention this because on Olimex's blog I found this recent post which describes their very inexpensive MOD-IO2, an "Input Output expandable board with UEXT".  This nice stackable design is the kind of approach to I/O  that I think should feature in all open hardware ARM boards, since its inherent expandability would allow a single community board to address a very diverse range of requirements that naturally appear in a large community.

Indeed, any computer board is made more flexible when it features a generic I/O connector, as Olimex described in their reason for UEXT ,which covers I2C, SPI and RS232.  Without generic I/O, you would have to offer different computer boards for different I/O requirements, which makes little sense.  This is obviously preaching to the converted here, but while it's normal to have expandible I/O connectors on the PC, it's far less common in the ARM world, other than through user-level USB.

I like what Olimex is doing in that area for microcontrollers, and it's very notable that they are continuing that flexible I/O concept on their application processor boards as well:  their A13-OLinuXino-WIFI-DEV features a UEXT connector.

Among application processor boards, TI's BeagleBone and Olimex's A13-OLinuXino seem to be in the lead for good I/O design.

Morgaine.

So far I'm happy with some of the tests using the iMX233 OLinuXino Maxi and Micro. I just added the headers to the Micro to set it on a protoboard, I'll post some pics later. Wating for the A13 that is expected to start shipping around Oct 20, and they are already testing the first prototypes for an A10 based board.

Not doing much yet with the iMX233 boards, just making sure the basic stuff works, that they don't crash, the Arch Linux images still need some work.

I agee with your assesment that BeagleBone and the OLinuXino have good I/O design.

-J

Morgaine Dinova wrote:

 

I mention this because on Olimex's blog I found this recent post which describes their very inexpensive MOD-IO2, an "Input Output expandable board with UEXT".  This nice stackable design is the kind of approach to I/O  that I think should feature in all open hardware ARM boards, since its inherent expandability would allow a single community board to address a very diverse range of requirements that naturally appear in a large community.

 

Indeed, any computer board is made more flexible when it features a generic I/O connector, as Olimex noted here as their reason for UEXT ,which covers I2C, SPI and RS232.  Without generic I/O, you would have to offer different computer boards for different I/O requirements, which makes little sense.  This is obviously preaching to the converted here, but while it's normal to have expandible I/O connectors on the PC, it's far less common in the ARM world other than through user-level USB.

 

I like what Olimex is doing in that area for microcontrollers, and it's very notable that they are continuing that flexible I/O concept on their application processor boards as well:  their A13-OLinuXino-WIFI-DEV features a UEXT connector.

 

Among application processor boards, TI's BeagleBone and Olimex's A13-OLinuXino seem to be in the lead for good I/O design.

 

Morgaine.

That looks similar to Digilent's (sp?) module. I think you need something a little more generic with more I/O defined on the interface. Then the bigger issue comes in getting a driver written and supported. If that could be done then you are really talking about something that would be useful for all of us.

I'm not worried about not seeing any pictures of boards from Freescale because we're talking about a "major" company with the funds and engineers to get things done. What Olimex is doing looks very promising too but I don't think they've been around as long as Freescale. If I had to sum up what I'm looking for it would be an embedded board with the processing power of a computer (i.e. dual core Arm), community supported OS and drivers, and the flexibility of an embedded board that provides direct access to GPIO and buses.

It seems that almost all of the current boards are leveraging off of the mobile phone markets and that ends up limiting the flexibilty

Sounds good, but put a microcontroller on the board alongside the applications processor.  Except for the most trivial of slow-speed applications, expecting Linux to handle low-level I/O without high response latency and jitter is a design mistake.

Microcontrollers cost next to nothing.  Use one, or indeed several.  The Linux kernel has better things to do.

George Ioakimedes wrote:

 

I'm not worried about not seeing any pictures of boards from Freescale because we're talking about a "major" company with the funds and engineers to get things done.

I wouldn't be worried about a Freescale board other than Freescale's habitual tardiness in delivering new ICs, a tradition they inherited from Motorola.  But I haven't seen any indication that Wandboard has any official relationship with Freescale other than as a customer for Freescale ICs.  For example, if I do a search at https://community.freescale.com for "Wandboard" I get no results.  (Plenty of results for i.MX6 Sabre.)  Just sayin'.

The Wandboard is not a child of Freescale. Check the company I posted the link before ...

And if you are smart enough and a good observer you will notice the names of the other main boards they produce: fairy, elf, druid, seer, wizard ...

-J

Yeah, I just noticed that this wasn't a Freescale project, in fact I can't even find any company name on that Wandboard web site which is odd...

I just posted this link in another mega-conversation about clusters, but also thought it might be appropriate to the conversation at hand here:

http://www.kickstarter.com/projects/adapteva/parallella-a-supercomputer-for-everyone?ref=category

Neil.

I think we mentioned Adapteva's Parallela before, it really looks promising. I'm glad they god funded (I'm a backer) at kickstarter, I exchange few messages with Andreas and they released more documentation and demos through the funding period.

Looking forward to see how they execute and the Parallela board comes out next year.

Similar to Kickstarter I recently contributed to cubieboard on indiegogo http://www.indiegogo.com/cubieboard?a=1678910

I did register for the Wandboard but didn't get any confirmation yet, on their blog they posted that the first batch of validation samples last week. http://www.wandboard.org/index.php/blog

And there are several others on the works, so we'll have plenty of ARM based boards to play with under the $100 price mark and I'm not sure we can compare some of the vis-a-vis with the Rpi.

I'm putting together a table, but there is already an interesting one on-line with the same idea

http://socialcompare.com/en/comparison/low-cost-arm-boards

-J

Yeah, my bad, I went back a few pages and realized I was late to the party... :-)

N.

Yeah, my bad, I went back a few pages and realized I was late to the party... :-)

N.