- Tue Jul 24, 2018 11:11 am
#199807
I'm trying out the Qwiic Pressure Sensor - LPS25HB. I think it has a problem with the temperature compensation.
It's hooked to a Raspberry Pi 3 via I2C. I'm reading the data registers in Python using example code from ControlEverythingCommunity. It's just a simple read and translate using a few smbus functions.
I have two other pressure sensors recording concurrently. They're all within inches of each other on the same breadboard. I'm also comparing data to a meteorological observing site less than 1 km away.
Anyway, the LPS25HB doesn't track the other sensors and all the variations match variations in temperature. This sensor is supposed to have temperature compensation built-in. There are no registers related to temperature compensation.
So the questions are: Is this a bad sensor? Is this sensor working as intended and the temperature compensation is just faulty? Or, have I somehow managed to read this thing in such a way as to undo the temperature compensation? (I'm not sure that's possible, but I'm open to suggestions.) Or, is something entirely going on.
One final question for anyone who has experience, is there any reason to suspect that the pressure readings would fluctuate with changes in voltage.
It's hooked to a Raspberry Pi 3 via I2C. I'm reading the data registers in Python using example code from ControlEverythingCommunity. It's just a simple read and translate using a few smbus functions.
I have two other pressure sensors recording concurrently. They're all within inches of each other on the same breadboard. I'm also comparing data to a meteorological observing site less than 1 km away.
Anyway, the LPS25HB doesn't track the other sensors and all the variations match variations in temperature. This sensor is supposed to have temperature compensation built-in. There are no registers related to temperature compensation.
So the questions are: Is this a bad sensor? Is this sensor working as intended and the temperature compensation is just faulty? Or, have I somehow managed to read this thing in such a way as to undo the temperature compensation? (I'm not sure that's possible, but I'm open to suggestions.) Or, is something entirely going on.
One final question for anyone who has experience, is there any reason to suspect that the pressure readings would fluctuate with changes in voltage.