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.

It's a complete different kind of attitude with Olimex and they share as much information as they have, not only the schematics but the full Eagle CAD files for their boards. They also recognize that don't know much or have much experience with Linux but are willing to work and test things people report to them.

I've been working and testing a panic issue with the iMX233 micro, very small board, plenty of GPIOs, they found that removing a resistor from one of the clock lines to the RAM fixed the inestability problem, after removing the resistor mine has been up and running for almost 24 hours.

I've also a iMX233 maxi under test that has been up for 5 days 15 hours.

Again this are not one to one comparable to the R-pi but it will become a very good alternative for some embedded applications where you want to have a light embedded Linux OS with some connectivity and plenty of GPIOs and don't care much about a high resolution graphics display.

The Olimex forum is very new, they just upgraded their website and are constantly working hard to improve their products and services, many of their boards can be obtanied from major distributors and are very responsive if you ask when they expect to have this or that. So far, interacting with them and their distributors have been a pleasure.

-J

BTW, I posted this picture somewhere else, showing some of the stuff (including a R-pi) I've currently for tests on my bench.

-J

Nice collection.

I was thing of getting an Ardunio Eleven to interface the RPi with some motors...What do you think?

By the way, if you're ordering direct from Olimex to the UK, I'd highly recommend the insured option.

Problem is, that costs a lot (for me anyway).

I've never had a problem buying stuff from elsewhere in Europe, US, Asia, but the Olimex one never arrived.

The local post is always reliable here.

They never e-mailed a notice of shipment, so when I queried them about it (just to ask shipping company), they replied

that it's not their responsibility, and left me to chase up with Bulgaria post (and still not being sure of the

shipment or where it was dispatched from to provide information to Bulgaria Post).

Since then, I've just purchased my boards elsewhere (e.g. I got a low cost AT91SAM7S blank PCB in a better form factor

for just a few dollars, and soldered the microcontroller on myself).

My e-mail to Olimex:

Hi,

It's been three weeks, but unfortunately the items still have not arrived. Which

postal firm was used for the airmail shipping, so I can check with Royal Mail

if they received it?

Many thanks,

Their response from their CEO:

Hi

this is Bulgarian post service, as written on our web AIRMAIL is post shipping with no tracking

usually it takes 1-2 weeks to arrive but sometimes it may take up to 5-6 weeks, this is outside our control and this is why on our web when your order with this shipment there is tickbox

"I understand that:

My order will be shipped with non-insured shipping service and Olimex cannot be held responsible for damaged, lost, or stolen packages."

Thanks, and that's just a very small part of the entire collection of evaluation/development boards, starter kits, etc.

I think that pariing the R-Pi with an Arduino is a great idea, also with other microcontroller based boards that can run a RTOS for better real time control, it also has the side effect that if you do thing right, thinkering with the I/Os on the Arduinio will limit potential damage on the R-Pi.

-J

Yup, shipping is a nightmare, particularly to/from some places in Europe, if you want to have tracking or better service it costs much more. I shipped a large number of boards from the US to Europe, Customs are always a pain in the butt, Italy particularly is horrible, UK is efficient but I had some cases where the customer was supposed to be notified to pick up a parcel and they never did, France is also problematic.

I'll stronlgy suggest you try to get your stuff from a local distributor, Farnell and Cool Components are Olimex's distributors in the UK.

-J

I agree on that, and there are some nice interfaces (I2C, SPI, asynch serial) for example which allow for compatibility between any interface board and any processor board (Rasp-pi, etc) since the rasp-pi has so few GPIO. TI seem to have some nice motor controllers, I've been looking into the DRV8432 (for an unrelated project), it needs maybe 6 GPIO, but I've yet to assemble up a board with that and a microcontroller. So much to do and so little time as always!

A third one is the fact that you need to properly shutdown the system to avoid sd card corruption.

That has very little to do with the Pi, the same would be true of linux (or windows) on your desktop/laptop if you just yank the power.

It's much more down to the trade offs you make by runing a full desktop oriented OS on what's essentially an embedded device.  Or put it another way, there's millions of xDSL routers, wifi AP's, android phones etc. that don't corrupt their flash storage when power unexpectedly goes away and they're mostly running linux too.

Of course they've been designed with that scenario in mind and have the OS specifically setup to handle it properly.

A third one is the fact that you need to properly shutdown the system to avoid sd card corruption.

That has very little to do with the Pi, the same would be true of linux (or windows) on your desktop/laptop if you just yank the power.

It's much more down to the trade offs you make by runing a full desktop oriented OS on what's essentially an embedded device.  Or put it another way, there's millions of xDSL routers, wifi AP's, android phones etc. that don't corrupt their flash storage when power unexpectedly goes away and they're mostly running linux too.

Of course they've been designed with that scenario in mind and have the OS specifically setup to handle it properly.