Interrupt latency.

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Giovanni
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Re: Interrupt latency.

Postby Giovanni » Sun Sep 08, 2019 3:29 pm

This small article could be of help: http://www.chibios.org/dokuwiki/doku.ph ... interrupts

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Re: Interrupt latency.

Postby Giovanni » Sun Sep 08, 2019 3:32 pm

Ah so you are using an M0, this topic started with an F4.

M0s do not support fast interrupts, you are always affected by system jitter. You may consider switching to an M3 or better.

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Re: Interrupt latency.

Postby mikeprotts » Sun Sep 08, 2019 4:55 pm

I don't think the original post included the processor family, I'd given my use of an F4 as an example, on the assumption that the processor in use would have had a similar capability.

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Re: Interrupt latency.

Postby rew » Wed Sep 11, 2019 7:11 pm

Giovanni wrote:This small article could be of help: http://www.chibios.org/dokuwiki/doku.ph ... interrupts

So you point me to a document that tells me how it's supposed to be done. No indication from you if what you see me do in my code posted above is OK or not.

Either you see me doing precisely what is required, but don't tell me about it, or you point me to that document because you spotted me doing something subtly wrong, where I don't see the difference with what I'm doing. A quick: "looks ok, but here are the docs" would have been nice.

The "short article" ends with "see the notes about the various ports.", and again no link. I don't think I actually need it now, but suppose I wanted to follow that "link", the procedure seems to be always: "Ask giovanni, he knows where things are documented".

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Re: Interrupt latency.

Postby Giovanni » Wed Sep 11, 2019 7:45 pm

That code tells nothing to me, it is so simple that I didn't need to comment about it and pointer you to the general solution for this kind of problems.

About where, here, all articles are here: http://www.chibios.org/dokuwiki/doku.ph ... cles:start
All the documentation is here: http://www.chibios.org/dokuwiki/doku.ph ... tion:start
The notes referred in that article are here: http://www.chibios.org/dokuwiki/doku.ph ... texm_notes

This is not the first time you come here complaining about the quality of the free support you are getting, I really suggest you put things in perspective, I am not getting paid to provide this service to you, if you have a customer id then please follow the proper channels.

If you find problems with the code or the documentation then the proper way is to post in "bug reports" about the problem without adding sarcastic comments.

In addition, when asking for support, I recommend, at very least, to specify what platform you are using and other relevant information like versions, compiler, environment etc.

Giovanni


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