[RFC] Ideas for ChibiOS/RT 3.0

This forum is dedicated to feedback, discussions about ongoing or future developments, ideas and suggestions regarding the ChibiOS projects are welcome. This forum is NOT for support.
User avatar
Giovanni
Site Admin
Posts: 13012
Joined: Wed May 27, 2009 8:48 am
Location: Salerno, Italy
Has thanked: 744 times
Been thanked: 620 times
Contact:

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby Giovanni » Sat Dec 08, 2012 11:49 am

OK, dropping support for small devices in ChibiOS/RT could become an option after creating this same support in NilRTOS. I am thinking to rename it to ChibiOS/NIL and make its API converge as much as possible, I am also thinking to make it entirely free, it also has educational potential because its simplicity.

The problem is that I couldn't support two distinct HALs, this is why I was thinking to an universal HAL usable with ChibiOS/RT and ChibiOS/NIL. This could become a non-problem if ChibiOS/NIL API becomes close enough to ChibiOS/RT.

Giovanni

User avatar
barthess
Posts: 861
Joined: Wed Dec 08, 2010 7:55 pm
Location: Minsk, Belarus
Been thanked: 7 times

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby barthess » Sat Dec 08, 2012 10:12 pm

Giovanni wrote:Real time counter handling moved in the Kernel from the HAL.

Good idea, but I am not sure it can be easily "standardized" and abstracted. For example, in my current project
I need tons of data packages timestamped with uS since Unix epoch. The mS resolution
is good enough so I use virtual timer and int64 counter. It increases every tick and corrected
every PPS pulse from GPS receiver. If I would need uS resolution than I have no way except
using dedicated HW timer, probably without any abstraction layers to gain reasonable perfomance.

Also I vote to C++ migration. Macros based abstraction interfaces looks too "obscured".

mabl
Posts: 417
Joined: Tue Dec 21, 2010 10:19 am
Location: Karlsruhe, Germany
Been thanked: 1 time
Contact:

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby mabl » Sat Dec 08, 2012 11:10 pm

barthess wrote:Good idea, but I am not sure it can be easily "standardized" and abstracted. For example, in my current project
I need tons of data packages timestamped with uS since Unix epoch. The mS resolution
is good enough so I use virtual timer and int64 counter. It increases every tick and corrected
every PPS pulse from GPS receiver.

While I understand the need - isn't that a bit over-engineered? Let's say you have a good standard crystal with 30ppm accuracy. If you count by us, after one second the time will be off by over 30000us=30ms, wouldn't it? Or am I just horribly too tired to see my logical error?

Freddie Chopin
Posts: 36
Joined: Wed Oct 17, 2012 8:57 am

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby Freddie Chopin » Sun Dec 09, 2012 9:41 am

1ppm = 1/10000 %, but for this case it's just easier to calculate with 1 point per milion, so for 30ppm resonator after 1s the result can (but doesn't have to) be off by 30us. I can't imagine how you got to a number that says a precise clock crystal resonator has an error of 3%...

4\/3!!

mabl
Posts: 417
Joined: Tue Dec 21, 2010 10:19 am
Location: Karlsruhe, Germany
Been thanked: 1 time
Contact:

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby mabl » Sun Dec 09, 2012 9:50 am

Indeed, I was too tired. I was counting in nanoseconds... sorry for the noise.

User avatar
barthess
Posts: 861
Joined: Wed Dec 08, 2010 7:55 pm
Location: Minsk, Belarus
Been thanked: 7 times

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby barthess » Sun Dec 09, 2012 11:27 am

mabl
I do not know how precise my crystal but 1mS error accumulates every 10-15 seconds.

User avatar
DeusExMachina
Posts: 223
Joined: Tue Apr 03, 2012 5:08 am
Location: South Korea
Has thanked: 3 times
Been thanked: 3 times

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby DeusExMachina » Wed Dec 12, 2012 5:27 pm

In my humble opinion it is a good idea to take more efforts on ARM devices. I think that these powerful MCUs need more freedom and speed for communication. So, the ethernet part (lwip) and services (http server, tftp, smtp) is a good point of development.

arsdmthe
Posts: 2
Joined: Sun Dec 02, 2012 4:14 pm

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby arsdmthe » Mon Dec 31, 2012 12:18 pm

eheh ;) 3.0 is very cool
missing only few thing to be as i want for tablets ;)
posix layer should not go in the kernel i think
what about a linux driver adaptator ???

rubenswerk
Posts: 104
Joined: Wed Feb 22, 2012 11:39 am
Location: Austria

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby rubenswerk » Mon Jan 21, 2013 1:08 pm

Giovanni wrote:[*]High Resolution Timer, the intervals handled by the kernel would not be milliseconds but a much higher resolution, this could become possible in a tickless kernel.
[*]Multicore support.
[*]Standalone ChibiOS with bootloader. The HAL would be handled as a separate project.
[*]Make 3.0 32bits only and optimize for it. NilRTOS could be targeted to the 8/16 bits space and be able to use the new HAL.[/list]

I like those ideas, especially focusing on 32 bit platforms (I use the AVR quite often, but I avoid using an OS for these projects).

About the multicore support:
I think that for hobby projects, multicore platforms will be quite unusual in the next years. In my job (infotainment) we started to use multicores, and it was hard work for the OS colleagues to only configure a third party OS. I guess it's a lot of work for Giovanni, but not that much users within next 5 years.

User avatar
levrik
Posts: 26
Joined: Wed Dec 21, 2011 7:35 am

Re: [RFC] Ideas for ChibiOS/RT 3.0

Postby levrik » Thu Jan 31, 2013 12:03 pm

Hi,
I found TLSF a very interesting Project. Perhaps this allocator could be added as a further option besides Memory-pools and heap-allocator.


Return to “Development and Feedback”

Who is online

Users browsing this forum: No registered users and 9 guests