[ECOS] How to handle serial port input?

[Jonathan Larmour]

Tom Vandeplas wrote:
> 
> Hi,
> 
> I'm working on a Cirrus edb7212 board. I would like to write a thread to
> handle input on the serial port. The ideal would be that the thread
> continues as long as there's data available.
> 
> I read the "simple serial" driver, as I understand any input to a serial
> port is written to a buffer by the kernel, by using "cyg_io_read" one can
> read this buffer... is this correct?
> 
> If this is correct, how can I know when to read this buffer, polling it all
> the time would be a disaster for performance. Is there some way to attach an
> interrupt to this or even better is there a synchrioniation primitive
> available?

You could have a separate thread that continuously does blocking reads. Or
you can instead use the fileio layer to give a POSIX style interface, and
use select().

Jifl
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