[SOLVED] How to interpret HAF sensor data?

Issue

My sensor i2c - (flow sensor) on raspberry pi gives a reading b'\x06g'. How can |I possibly interpret this? Code snippet used (this code is based on - href="https://github.com/stripemsu/HoneywellFlow" rel="nofollow noreferrer">https://github.com/stripemsu/HoneywellFlow)

import io, fcntl

I2C_SLAVE=0x0703
I2C_BUS=1
HAFAddr=0x49
maxflow=100 #100 sccm
toHex = lambda x: ''.join([hex(ord(c))[2:].zfill(2) for c in x])
i2c_r=io.open("/dev/i2c-"+str(I2C_BUS),"rb",buffering=0)
i2c_w=io.open("/dev/i2c-"+str(I2C_BUS),"wb",buffering=0)
fcntl.ioctl(i2c_r, I2C_SLAVE,HAFAddr)
print(i2c_r.read(2))
i2c_r.close()

I have uploaded the datasheet of the sensor HERE

Solution

Doing b'\x06g'.hex() gives 0x0667 (converts bytes codes to hex representation).

Seems like the data you are getting is 0x0667, or 0b0000 0110 0110 0111. The page 6 of the datasheet gives the digital output vs flow scale. 0x0667 is roughly 10% of the maximum. (in decimal, it can be interpreted as a value of 1639 over the maximum possible value of 16384 (2^14)).

So, the simplest interpretation you could do is to calculate the ratio of the obtained value over the maximum output value (2^14, or 16384). This will probably not give optimal results though, I'm sure some sort of calibration is needed and is surely described in details in the datasheet.

Answered By - DarkFranX

Answer Checked By - Mildred Charles (WPSolving Admin)