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RE: Serial Latency Issues, Baud Rate Affects Buffering
>I'll give 2.4.22 a shot.
>Is the 2.4.22 on your website different from the official sources from
On the website we have a patch compared to 2.4.22. The patch contains
e.g. a newer serial port driver. In 2.4.25 the official sources will
contain the serial driver patches. Takes a while to get our stuff
into the official trees.
PS. As Johan already mentioned you can never trust that you will get
7 characters at each iteration. User space has no guarantees what
so ever. DS.
From: email@example.com">mailto:firstname.lastname@example.org] On
Behalf Of Eric Sorton
Sent: Friday, January 09, 2004 9:16 PM
To: Johan Adolfsson; dev-etrax
Subject: Re: Serial Latency Issues, Baud Rate Affects Buffering
On Friday 09 January 2004 14:53, you wrote:
> Note the "to see if we should force DMA to flush" in the help text,
> which make it consistent with the code - "we should" is only true
> if no data has been received since the last check.
> You could modify force_eop_if_needed() I guess, but I wouldn't
I had already tested adding FLUSH_EOP() to force_eop_if_needed() prior
receiveing this message. It definately improved the latency :-)
Is the only drawback performance? Or am I going to have "other"
> Not any more, it's implemented in the 2.4.22 kernel along with other
I'll give 2.4.22 a shot.
Is the 2.4.22 on your website different from the official sources from
Thanks for your help,
Senior Member Research Staff
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