Re: (Big) problems achieving fair scheduling of a semaphore ISR producer - thread consumer case

Paul Sokolovsky

On Fri, 7 Apr 2017 09:06:14 +0100
Daniel Thompson <> wrote:


So, it's a typical "nothing works" type of bug each of us faced and
enjoyed. I really need 2nd (3rd, 4th) opinion on this. My kind
request though is: please don't try to shift it all on UART and
talk about the need of DTR/RTS, etc. UART is damn slow device by
the current standards, which should "just work" with dozens-of-MHz
CPUs without any flow control on hardware side.
If the UART TX side produces more characters than it receives in
input then flow control (or very large buffers) are the *only* way to
avoid losing characters when the input is running at maximum speed.
OMG, so do you want to say that the problem is that we use busy-polling
for UART TX??

Best Regards,
Paul | Open source software for ARM SoCs
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