RPi with Sensirion flow meter (I2C) - Raspberry Pi Forums

hi,

i'm trying sensirion smf3000 flow sensor (i2c) work rpi.

senrsor: https://www.sensirion.com/products/mass ... low-meter/

i2c data sheet: https://www.sensirion.com/fileadmin/use ... n_v1.1.pdf

have got i2c enabled on rpi , can detect sensor correct address (0x40). have kind of communication going between sensor , rpi without errors, data don't make sense me , static regardless of te flow.

far understand want me start measurement writing address 0x40 2 bytes 0x1000. new measured value should read 3 bytes (including crc checksum) same address 0x40.

how do simple steps? don't think i've found suitable functions. far i've tried:

code: select all

import time import smbus  i2c = smbus.smbus(1)  address = 0x40 cmd_start = 0x1000 cmd_serial = 0x31ea cmd_soft_reset = 0x2000  i2c.write_word_data(address, 0x00, cmd_soft_reset) time.sleep(0.1) i2c.write_word_data(address, 0x00, cmd_start)  try:     while true:         time.sleep(.03)         msb = i2c.read_i2c_block_data(address ,0x00)         print (msb)         msb = i2c.read_word_data(address, 0x00)         print (msb)         msb1 = i2c.read_byte(address)         msb2 = i2c.read_byte(address)         msb3 = i2c.read_byte(address)         print (str(msb1) + " " + str(msb2) + " " + str(msb3))  except keyboardinterrupt: # ctrl+c pressed, so...     print ("bye") 

, lot of this...

code: select all

[16, 19, 126, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255] 4880 16 16 16 

there way send , receive several bytes without defining target register?
or problem somewhere else?


in advance

i know it's been on year, wondering if able find solution, experiencing same issue. thanks.

raspberrypi