1. I2C (Inter-Integrated Circuit)

I2C is a 2-wire, address-based protocol. It uses SDA (Data) and SCL (Clock) lines. Because it is addressable, you can connect dozens of sensors to the same two pins.

Scanning the I2C Bus

Before communicating with a sensor, you can “scan” the bus to find its unique hexadecimal address.

import { I2C } from 'intarva';

const i2c = new I2C(0, { sda: 'GP4', scl: 'GP5' });
const devices = i2c.scan();
console.log('Found devices at:', devices.map(d => '0x' + d.toString(16)));
                    

from machine import I2C, Pin

i2c = I2C(0, sda=Pin(4), scl=Pin(5))
devices = i2c.scan()
print('Found devices at:', [hex(d) for d in devices])
                    

2. SPI (Serial Peripheral Interface)

SPI is a 4-wire, high-speed protocol used for displays and SD cards. It uses MOSI, MISO, SCK, and CS (Chip Select). Unlike I2C, it is significantly faster but requires a dedicated CS line for every device.

3. Choosing the Right Protocol