Wire.h File Reference

Arduino Wire (I2C) on the SDA/SCL header pins. More...

#include "Arduino.h"
#include "api/HardwareI2C.h"
#include "api/RingBuffer.h"
#include "hardware/i2c.h"

Go to the source code of this file.

Classes
class	PhyduinoWire
	I2C controller or peripheral on one RP2040 I2C peripheral; sketches use Wire. More...

Variables
PhyduinoWire	Wire
	I2C on the header SDA / SCL pins.

Detailed Description

Arduino Wire (I2C) on the SDA/SCL header pins.

• Controller: begin(), beginTransmission(), write(), endTransmission(), requestFrom(), read().
• Peripheral: begin(address) with onReceive() / onRequest().

The board has no I2C pull-up resistors; the RP2040's weak internal pull-ups are enabled, which is enough for short wires at 100 kHz. Add 4.7 kOhm resistors to 3.3 V for longer buses or 400 kHz.

Peripheral and pins: pins_arduino.h (PHYDUINO_WIRE_INSTANCE, PIN_WIRE_*).