Re: Stupid user with user-space questions, matrix LED driving with user space code only.

From: el es
Date: Mon Feb 18 2013 - 06:55:58 EST

Jonathan Andrews <jon <at>> writes:

> What about a yield alignment mechanism for user space. IE the process
> calls the kernel with a request "schedule me first after a yeild" - then
> the process at least has whatever the timer granularity is to do
> something timing critical... add a flag to ignore or defer interrupts
> and you have a semi 'hard-realtime' behaviour for user space, allowing
> user space to grab small chunks of real time. Yes a nasty looking
> facility for SMP intel servers but really useful for embedded.

Seems you have some (bad?) habits from embedded programming,
you think Linux is FreeRTOS ;)

Linux as such, as far as I read, is not a real-time OS, it will
NOT do what you want in userspace, (maybe unless you build it with
the RT patchset?)

Better take the advice and go build a kernel driver for this display.

Or use a small microcontroller that won't have the limitations.

> Thanks,
> Jon

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