LM75AD temperature sensor~
This feature is included only in tasmota-sensors
and tasmota32
binaries
When compiling your build add the following to user_config_override.h
:
#ifndef USE_LM75AD
#define USE_LM75AD // [I2cDriver20] Enable LM75AD sensor (I2C addresses 0x48 - 0x4F) (+0k5 code)
#endif
The LM75AD is an I2C temperature sensor that converts temperature directly to digital signals from -55°C to +125°C and achieves an accuracy of 0.125°C
Some features of the LM75A chip not implemented in this driver:
- Programmable temperature threshold and hysteresis set points - Stand-alone operation as thermostat at power-up
The STDS75 chip is functionally identical to the LM75A, and can be interfaced using the same code as the LM75A.
Configuration~
Wiring~
LM75AD | ESP |
---|---|
VCC | 3.3V |
GND | GND |
SDA | GPIOx |
SCL | GPIOy |
OS | not used |
The driver currently only allows the use of a single LM75AD sensor on any of the addresses configurable through pins A0, A1 and A2. These are conveniently broken out on the breakout board either as pins or as solderable joints as can be seen on the example breakout board.
These pins need to be tied down to either GND or VCC (3.3V) and the resulting I2C address will be set during power-up according to the table:
Tasmota Settings~
In the Configuration -> Configure Module page assign:
- GPIOx to
I2C SDA
- GPIOy to
I2C SCL
After a reboot the driver will detect LM75AD automatically and display Temperature.
Commands~
TempOffset
can be used for calibrating the measured temperature. This setting affects all temperature sensors on the device.
Breakout Boards~
Can also be used standalone if soldered to a board given the diagram is used
R1 and R2 are pull-up resistors which are required by the I2C bus to operate properly. If you have other I2C sensors with pull-up resistors connected to the same I2C bus it's probably not necessary to have them.