Part 3: http://www.eeweb.com/blog/robert_berger/arduino-for-mere-m0rtals-part-3

0.01% of Arduino users is still a big number at least compared to others!

Have a look at my article http://www.eeweb.com/blog/robert_berger/arduino-for-mere-m0rtals-part-2 and scroll down a  bit to google trends.

If you do a google search for arduino you get about 15,700,000 results (0.26 seconds).

Let's see what the future brings and also how well arduino will be accepted by "professionals" who know how to program. Besides, as you say, once you understand the concepts of multi-threading it's much easier than poking around in ISR and re-inventing semaphores, mutexes and message queues...

Regards,

Robert

Part2: http://www.eeweb.com/blog/robert_berger/arduino-for-mere-m0rtals-part-2

Hi,

I wanted to use "for dummies" for articles and the copyright holders actually told me how much I needed to pay to use it, so I came up with "mere m0rtals" instead.

I have no idea how much it would cost to make this a trademark, but would only make it a trademark/or copyright it to make sure that it be used forever for free for everyone.

Regards,

Robert

Part 1: http://www.eeweb.com/blog/robert_berger/arduino-for-mere-m0rtals-part-1

[Update2]

Hi,

Update2 Upload to arduino (using bootloader only)(windows 64 bit only)

Why shouldn't this work on Linux as well?

Regards,

Robert

@fat16lib:

It's not that hard to use FreeRTOS.  I downloaded FreeRTOS and did a few edits to make it compatible with Arduino.  I made FreeRTOS an Arduino library, AvrFreeRTOS.  It took about an hour.

This sounds interesting.
Is this available somewhere for download?

Regards,

Robert

Concerning the existing libraries and an (RT)OS:

The solution which would most likely deliver the best results performance wise would IMHO be a rewrite of the current libraries, but there is more than one way to skin a cat.

The solution with the highest degree of reuse-ability of existing libraries would most likely be just a "partial rewrite" which comes with some performance trade offs. This solution is what the DruinOS people had in mind.

In the Microchip AppNote AN1264 is more information about how this could be done:
http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=1824&appnote=en544728

Regards,

Robert

@pito:

You wrote: "the biggest issue with rtos-es is the availability of drivers for ie. i2c, spi, uart, etc".

Talking about Arduino. It's biggest strength is exactly what you see as the biggest issue with RTOS-es.

Hence my idea to combine both.

Wouldn't it be great to have a RTOS with an Arduino API or Arduino with a RTOS?

If this is something more people are interested in I believe it's doable and in order to minimize most of the troubles you have with drivers and RTOS-es it would be good to put hooks into the Arduino libraries from now on and not as an afterthought.

What I mean is, that we could create libraries where the shared resources are protected by macros, which expand to nothing when you don't use any RTOS and which expand to something when a RTOS is used. Also we could actually get a performance gain under certain circumstances by using a RTOS because there will be no need for polling and the CPU could be given to other tasks.

Anyhow these are just preliminary thoughts and we'll need more discussions and a careful design.

Regards,

Robert

@westfw

I don't know threadkit, but judging from what I can see from the sources it's very limited because it is a cooperative scheduler and not a preemptive one and lacks interprocess communication primitives like e.g. semaphores, mutexes and queues.

Regards,

Robert

@bubulindo:

I have an Arduino UNO and DruinOS, which is derived from FreeRTOS, running happily on it.

FreeRTOS is a real RTOS and supports 8 bit microcontrollers like 8051, AVR, PIC18. I just ported it to a 18lf45k22 just because people were telling me that this is not possible 

It certainly adds a few percent of overhead for those little machines, but I'm more after the concept of programming in threads compared to the superloop, as it is typical for the Arduino.

Projects are usually growing and having an RTOS just helps to break things into tasks and to add new tasks without seriously affecting the timing.

Hey I'm a geek and use a RTOS even on small microcontrollers

... but as bigger microcontrollers are getting cheaper and cheaper it's certainly a topic we should look into a bit to be ready to roll on future Arduino boards ...

Regards,

Robert

Hi,

On the old forum I came across DruidOS (FreeRTOS+Arduino) http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1256745982/180 which seems to be a bit outdated and orphaned, although it looks like a very nice solution to bring multithreading to Arduino.

With the upcoming much more powerful Arduino boards (ARM and friends) we will be able to tackle more complex problems and all the great Arduino libraries plus a RTOS might be helpful. Also if we would have multithreading in mind from the beginning the libraries could be designed accordingly from the beginning and there would be no need to add somehow multithreading support to them as an afterthought like it is right now.

Is there going to be any Arduino officially supported multithreading solution?

Is someone interested in maintaining DruidOS?

Please advise.

Regards,

Robert