[Voyage-linux] reading temperature

[Stéphane Acounis]

Le Wed, 25 Mar 2009 08:59:42 -0500
Jeff Ramin <jeff.ramin at singlewire.com> a écrit:

> 
> Using voyage 0.5.2 on an ALIX board...does anybody know how
> to get the current temperature off the board?
> 

Yes, it's explained in the README file:

4.2 ALIX support
======================

4.2.1 Temperature sensors for ALIX.1 and ALIX2/3
================================================
When running Voyage Linux with ALIX, choose ALIX profile in voyage
update, the required modules would be added to /etc/modules.  It adds
the following modules in /etc/modules:
        w83627hf
        lm90
        geodewdt

ALIX.1 board uses w83627hf driver while ALIX.2/3 uss lm90.  You can get
the temperature reading from sensors program, or get the values from
sysfs:

(for ALIX.1)
        cat /sys/bus/i2c/drivers/w83627hf/9191-0290/temp1_input
        cat /sys/bus/i2c/drivers/w83627hf/9191-0290/temp2_input
        cat /sys/bus/i2c/drivers/w83627hf/9191-0290/temp3_input

You may also use sensors utility to get the temperature reading.  If
temp1 reading may not be ready at boot up, you need to modify w83627hf
section in /etc/sensors.conf:

chip "w83782d-*" "w83627hf-*"
...
        set sensor1 1

Known Issue: the readings returned from w83627hf is not very accurate.
temp1 reading is too low (~30C) and some offset should be applied.  But
temp1 reading can move down to 20C if you apply cooling agent on the
Geode processor.  temp2 and temp3 do not move up or down too much at
idle or under high low.

(for ALIX.2/3)
        cat /sys/bus/i2c/drivers/lm90/0-004c/temp1_input
        cat /sys/bus/i2c/drivers/lm90/0-004c/temp2_input


-- 
Stéphane ACOUNIS
SUBATECH Nantes - Service d'Électronique
Tél: 02-51-85-84-28  06-64-62-99-20

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