BORA SOM/BELK-L/Pheripherals/Temperature sensors

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Temperature sensors[edit | edit source]

Bora SOM has a TMP421AIDCN temperature sensor onboard.

The following commands can be issued from command line in order to get the SOM temperatue:

  • read the PCB temperature
root@bora:~# cat /sys/devices/soc0/amba/e0004000.i2c/i2c-0/0-004f/hwmon/hwmon1/temp1_input

the returned value has to be divided by 1000 for a °C temperature

  • read the CPU temperature
root@bora:~# cat /sys/devices/soc0/amba/e0004000.i2c/i2c-0/0-004f/hwmon/hwmon1/temp2_input

the returned value has to be divided by 1000 for a °C temperature

Moreover, the SOC has an internal temperature sensor device which can be read using the following shell script:

root@bora:~# cat temp.sh
#!/bin/sh

# Tcpu
TEMP_RAW=`cat /sys/devices/soc0/amba/f8007100.adc/iio:device0/in_temp0_raw`
TEMP_OFFSET=`cat /sys/devices/soc0/amba/f8007100.adc/iio:device0/in_temp0_offset`
TEMP_SCALE=`cat /sys/devices/soc0/amba/f8007100.adc/iio:device0/in_temp0_scale`
TEMP=`awk "BEGIN {print (($TEMP_RAW+$TEMP_OFFSET)*$TEMP_SCALE)/1000}"`

echo "Cpu Temp: ${TEMP}"