Introduction to I2C

Learn about I2C communication protocol and how to use it with the Raspberry Pi Pico and MicroPython.

By Kevin McAleer,    3 Minutes

Introduction

Welcome to Lesson 12 of the Raspberry Pi Pico with MicroPython - GPIO Mastery course. In this lesson, you will learn about the I2C (Inter-Integrated Circuit) communication protocol and how to use it with the Raspberry Pi Pico and MicroPython. I2C is a common communication protocol used to connect microcontrollers to other devices such as sensors, displays, and EEPROMs.

What is I2C?

I2C is a communication protocol used to transmit and receive data between two devices. It is a synchronous protocol, which means that the transmitter and receiver are synchronized by a clock signal. It uses two wires for communication: SDA (Serial Data) and SCL (Serial Clock).

Setting up I2C on Raspberry Pi Pico

To use I2C on your Raspberry Pi Pico board, you will need to enable the I2C interface and configure the I2C pins. Follow these steps to set up I2C:

1. Enable I2C on your Raspberry Pi Pico board using the machine.I2C module.
2. Configure the I2C pins using the init method.
3. Use the scan method to detect the address of connected devices.

Here’s an example of setting up I2C on the Raspberry Pi Pico:

from machine import Pin, I2C

# Initialize I2C
i2c = I2C(0, scl=Pin(1), sda=Pin(0), freq=400000)

# Scan for I2C devices
devices = i2c.scan()
print(devices)

Using I2C in MicroPython

Once you have set up I2C on your Raspberry Pi Pico board, you can use it to communicate with other devices. Here’s an example of reading data from an I2C device:

# Read 2 bytes of data from register 0x0F of the device with address 0x68
data = i2c.readfrom_mem(0x68, 0x0F, 2)
print(data)

And here’s an example of writing data to an I2C device:

# Write 1 byte of data (0x01) to register 0x10 of the device with address 0x68
i2c.writeto_mem(0x68, 0x10, b'\x01')

Conclusion

In this lesson, you learned about the I2C communication protocol and how to use it with the Raspberry Pi Pico and MicroPython. You also learned how to set up I2C on your board and how to use it to communicate with other devices. You can use this knowledge to create a variety of projects that involve communicating with other devices using I2C.