Christian Magnusson <mag <at> mag.cx> writes:

> You can download the packages from my temporary repository if you want at:
> http://home.mag.cx/nslu2/packages/
> 
> owfs_2.6p5-15_armeb.ipk
> owlib_2.6p5-15_armeb.ipk
> 
> This new version defaults into flexible speed, which makes it possible to
> set the slewrate to a lower value than 15V/us.
> This should lower the risk to get signal-distortion in the cables,
> especially when it's a bigger 1-wire network.
> 
> echo 0 > /tmp/1wire/bus.0/system/adapter/overdrive.0   for regular speed
> (always 15V/us)
> echo 1 > /tmp/1wire/bus.0/system/adapter/overdrive.0   for flexible speed,
> slewrate tunable.
> echo 2 > /tmp/1wire/bus.0/system/adapter/overdrive.0   for overdrive speed
> (always 15V/us)
> 
> Can you try this new version and tell me if your crc-errors disappears?
> 
>
Christian,
after the installation of 2.65-15 version of owfs, i checked the value of
/tmp/1wire/bus.0/system/adapter/overdrive.0 and i found a 0 (zero) there.
Reading your posting i understand that, to be able to change the slew param, i
must put a 1 on the overdrive.0 parameter.
I issued a echo 1 > /tmp/1wire/bus.0/system/adapter/overdrive.0 and then i start
tweeking the /tmp/1wire/bus.0/system/adapter/pulldownslewrate.0 parameter
ranging from 0 up to 7.
The problem is still there but the errors are changed . 
The output of grep -v " 0" /tmp/1wire/bus.0/statistics/errors/* is now :

/tmp/1wire/bus.0/statistics/errors/BUS_select_low_errors:          24
/tmp/1wire/bus.0/statistics/errors/CRC8_tries:           5

Actually i am tweeking even the other parameter you indicated in a previous
posting : writeonelowtime.0 and datasampleoffset.0, i don't see any difference
on the behaviour of the NSLU2.

I don't know if it make sense, i made the same test with
/tmp/1wire/bus.0/system/adapter/overdrive.0 set to 0 and 2 with the same results
as before.

Just a little remark: as said before , my network is composed by just two
devices, the Bus master and the 2408 board. The twos are connected via a short
(no more than 30 cm) rj45 cable.
Regards
Giuliano


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