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LM75 temperature sensor module

lm75.jpg

This an LM75 on a small board for the Raspberry Pi.

It's not very accurate.

CONFIG

dtparam=i2c_arm=on
#dtparam=i2c_vc=on

TOOLS

apt install i2c-tools lm-sensors

TEST

i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- 48 -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

SETUP

echo lm75 0x48 > /sys/class/i2c-adapter/i2c-1/new_device
find /sys/class/i2c-adapter/i2c-1/1-0048/hwmon/
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/device
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/temp1_max
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/subsystem
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/update_interval
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/power
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/power/runtime_suspended_time
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/power/autosuspend_delay_ms
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/power/runtime_active_time
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/power/control
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/power/runtime_status
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/temp1_max_hyst
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/uevent
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/temp1_input
/sys/class/i2c-adapter/i2c-1/1-0048/hwmon/hwmon2/name
watch -n 1 /usr/bin/sensors

MEASURE

Every 1.0s: /usr/bin/sensors

lm75-i2c-1-48
Adapter: bcm2835 (i2c@7e804000)
temp1:        +31.5°C  (high = +80.0°C, hyst = +75.0°C)

cpu_thermal-virtual-0
Adapter: Virtual device
temp1:        +38.9°C

rpi_volt-isa-0000
Adapter: ISA adapter
in0:              N/A
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