Re: Dropped characters in serial connection without flow control

From: Greg KH
Date: Wed Oct 28 2009 - 14:08:44 EST


On Wed, Oct 28, 2009 at 06:59:37PM +0100, Peter Stuge wrote:
> Peter Stuge wrote:
> > I'm writing a line discipline for a serial port multiplexing
> > hardware
>
> There is no(!) support for flow control in the hardware.
>
> Is there anything I can do to reduce serial port interrupt latency or
> otherwise try to mitigate this in my ldisc or in Linux in general? I
> realize that it will never be quite reliable without any flow
> control.

What's wrong with XON/XOFF? That is a well-known flow control protocol
for systems without hardware support for it.

And since when is adding a UART to a hardware chip expensive these days?

thanks,

greg k-h
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