Bosch barometer series accuracy - Raspberry Pi Forums

hi,

suppose famous barometer sensor affordable on market barometer sensor series bosch.

bought tens of bmp085, bmp180 breakout board adafruit , found weird. value of temperature , pressure coming each bmp180 different.

instance sensor giving

code: select all

temperature = 27.90 *c pressure = 100274 pa altitude = 87.70 meters pressure @ sealevel (calculated) = 100276 pa real altitude = 101.90 meters

sensor b giving

code: select all

temperature = 27.30 *c pressure = 100317 pa altitude = 84.60 meters pressure @ sealevel (calculated) = 100312 pa real altitude = 99.04 meters

sensed @ same time in same place on same breadboard.

used adafruit bmp library apparently compensating sensed value calibration table in eeprom.

normal?

no way make accurate in absolute representation? i'm planning use bosch barometer sensor localize statically deployed rpi if fetching accurate value sensor impossible, need find out plan b.
fyi, relative pressure variation ok when mobilize sensor moving between floors. senses floor change.
problem variation of sensed value among sensors in same place , condition.

each genuine bosch bmp180 sensor supposed have it's own calibration data. read , use returned values in complex maths temp , pressure.

try using
https://github.com/keiichishima/rpisens ... /bmp180.py

raspberrypi