Change I2c adress for SLF3S-0600F Liquid Flow Sensor

Hello everyone,

I have ordered three flow sensors of type SLF3S-0600F which I want to use to monitor the flow inside a microfluidic channel, and I am not sure if it is possible to change their I2C addresses through software. The data sheet talks about a soft reset command (page 12) which is described in the I2C-bus specification and user manual (page 17) but I don't know if with this command I can actually can change the address or not.

Can someone please have a look at my code and tell me if it makes sense

#include <Wire.h> // Arduino library for I2C

void setup() {

Serial.begin(9600); // initialize serial communication
Wire.begin(); // join i2c bus (address optional for master)

Wire.beginTransmission( 0x00); // General call
Wire.write( 0x06); // Soft reset
Wire.write( 0x30); // new I2C address
Wire.endTransmission();

delay(50); // wait long enough for chip reset to complete
}

Data sheet flow sensor:
https://www.mouser.de/datasheet/2/682/Sensirion_Liquid_Flow_Sensors_SLF3S_0600F_Datashee-2507286.pdf

I2C-bus specification and user manual:
https://www.nxp.com/docs/en/user-guide/UM10204.pdf

The sensor’s I2C address is 8.

Looks like there is only one address possible. To use multiple units I think you will need an I2C multiplexer.

Here is an 8-channel I2C multiplexer on a breakout board for $6.95:

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Thank you John!

Welcome to the forum.

The manufacturer's page of the flow sensor: https://sensirion.com/us/products/catalog/SLF3S-0600F/.
There are many documents on that page and even a link to a library for Arduino on Github. That library uses a fixed I2C Address: static const uint8_t SLF3X_I2C_ADDRESS = 0x08;

Some sensors can change their I2C address, but this sensor does not mention that.
I was already shivering and sweating, because that is often hard to do, but I can relax now, the sensor can not change its I2C address.

A "general call" is mentioned in the I2C standard. It is not often used. This sensor uses the "general call" for a soft-reset. I guess that is allowed, but I don't know if that is a good thing or a bad thing.

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Thank you Koepel!

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