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Table of Contents
Check Device I2C Address
Aug 2026
Introduction
When you attach a device on the I2C bus, even though you might know it's address, it's a great idea to run a test to see if you can read it's actual address.
In this example, I have an LCD address on I2C bus zero, and I know it's address is 3C0 Hex, which in decimal is 60.
I2C Address Check
Below is the code we need to run to check for devices on the I2C.
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from machine import Pin, I2C i2c = I2C(0, scl=Pin(5), sda=Pin(4), freq=200000) print("I2C addresses:", i2c.scan())
There are a couple of considerations around this code, and they are:
- i2c = I2C(0 - The Zero is for Bus 0
The Pico has Bus 0 and Bus 1, and you should know which you used.
- scl=Pin(5), sda=Pin(4)
These are the Pico pins your device is connected to, so scl(5) is Pico Pin 7 and sda(4) is Pico pin 6.
If you run the code above, you will see something similar to below:
Here we can see