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Kjell Claesson wrote:
<blockquote
cite="mid:200908281807.01451.kjell.claesson@epost.tidanet.se"
type="cite">
<pre wrap="">OK David,</pre>
<blockquote type="cite">
<pre wrap="">Kjell,
Thanks for your time in replying.
The cable is a regular commercial shielded cable and is only six feet
long. Grounding should not be an issue, everything is on a single
circuit with a single ground and is powered through the UPS itself, all
in one cabinet, so all grounds should be at the same potential.
</pre>
</blockquote>
<pre wrap=""><!---->That is good. Should not be any problems.
Then the problem may be the polling frequency. The ups is sending
a lot of data for each request. But as you are running it at 19200 it should
be OK.
I have my PW5125 on 9600 bps and have no problem.
What is your system spec ? Linux freebsd ?
Kernel version ?
I think there was some glitch around version 2.6.25 of the kernel
that make the serial port behave strange.
</pre>
</blockquote>
# uname -rvmpio<br>
2.6.29.1-smp #1 SMP Fri Apr 10 14:22:00 EDT 2009 i686 Intel(R)
Pentium(R) 4 CPU 3.00GHz GenuineIntel GNU/Linux<br>
<br>
The system is Slackware 12.1 with an updated kernel I compiled from
source.<br>
<br>
Should I try changing the polling frequency just to see if it helps?<br>
<br>
<blockquote
cite="mid:200908281807.01451.kjell.claesson@epost.tidanet.se"
type="cite">
<pre wrap="">
Can you relate the errors in the log to any activity? Is the time random
or is it spread evenly over time ?
</pre>
</blockquote>
I am not getting any other errors or events or significance or that
correspond with the UPS errors. The comm errors are not continuous, but
there doesn't seem to be a strict pattern. They seem to cluster one
every minute or two for between two and ten minutes at a time, with
periods of between a half hour to an hour of quiet between the clusters.<br>
<br>
David<br>
<br>
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