Grove - Barometer Sensor values

Products & Technology Grove
#1

I recently purchased a Grove - Temp&Humi&Barometer Sensor (BME280), but the readings it produces are not correct.

Its connected to a Raspberry Pi 4 using I2C and powered by 5V supply from the PI pins.

I tried a few libraries for interfacing with the BME280 using Python.

groveBME280RPi

PyPi bme280 v0.6

Both produce (same) incorrect values, for some reason.

DIG_T1: 16563 DIG_T2: 26491 DIG_T3: -4093

Raw ADC Reading: [‘0x4e’, ‘0xbb’, ‘0x30’, ‘0x7c’, ‘0x97’, ‘0xd0’, ‘0x5a’, ‘0xa1’]
Translates to: adc_P: 322483 adc_T: 510333 adc_H: 23201
Converted to SI units: Temperature: 74.67C, Humidity: 0.00%, Pressure: 658.57hPa

The board is all default, without any configurations. I was expecting something closer to 21C / 80% rel and 1016 hPa

Can someone tell me what I am doing wrong?

#2

Hi,slb:
Did you follow the example in the Wiki?
In addition, can you provide the data you got and the actual temperature data from the thermometer? It helps me a lot to help you figure out the problem.

btw,The sensor is not necessarily sent to you as soon as it is produced, so it may have been placed in the warehouse for a long time, so it is not excluded that there is an aging problem. If this is the reason, you can contact the after-sales service for repair and refund

#3

Hi Jostar,

Thank you for your reply! I connected it to a Raspberry PI using the I2C interface and not to an Arduino. The Raspberry detects it fine on the bus with the expected address. The two linked drivers are able to read/write bytes and perform the calculations as described in the BME280 data sheet.

Unfortunately, the values are way off.

I belive I did include as much as I could; please let me know what else I could include
Calculated Temperature: 74.67C

BME280_REG_DIG_T1: 16563
BME280_REG_DIG_T2: 26491
BME280_REG_DIG_T3: -4093

ADC Reading in bytes: [‘0x4e’, ‘0xbb’, ‘0x30’, ‘0x7c’, ‘0x97’, ‘0xd0’, ‘0x5a’, ‘0xa1’]
Translates to: adc_P: 322483 adc_T: 510333 adc_H: 23201

As far as I can tell, those are all the values included in the temperature calculation.

#4

Hi, have you tried thel ibary of Seeed?
GitHub - Seeed-Studio/Grove_Barometer_HP20x: Grove_Barometer sensor using HopeRF’s HP20x

#5

Hi Jostar,

I have not - as far as I can tell it is for a different sensor? Grove - Temp&Humi&Barometer Sensor (BME280) is based on the Bosch BME280 and the library is for HopeRF HP206C. Unless I am misunderstanding something.

#6

Hi, I’m sorry this one is. The last post was for a normal pressure sensorGitHub - Seeed-Studio/Grove_BME280