Nano RP2040 Connect Cheat Sheet

The Arduino® Nano RP2040 Connect is a development board in Nano format, based on the RP2040 microcontroller. It features a Wi-Fi / Bluetooth® module, a 6-axis IMU (Inertial Measurement Unit) with machine learning capabilities, a microphone and a built-in RGB.

This article is a collection of guides, API calls, libraries and tutorials that can help you get started with the Nano RP2040 Connect board.

You can also visit the documentation platform for the Nano RP2040 Connect.

Core

The Nano RP2040 Connect uses the Arduino Mbed OS Nano Boards core.

Datasheet

The full datasheet is available as a downloadable PDF from the link below:

• Download the Arduino Nano RP2040 Connect datasheet

Installation

Arduino IDE 1.8.X

The Nano RP2040 Connect can be programmed through the Classic Arduino IDE 1.8.X. To install your board, you can check out the guide below:

• Installing the Arduino Mbed OS Nano Boards core

Arduino IDE 2.0.X

The Nano RP2040 Connect can be programmed through the Arduino IDE 2.0.X. To install your board, you can check out the guide below:

• How to use the board manager with the Arduino IDE 2.0

Web Editor

The Nano RP2040 Connect can be programmed through the Web Editor. To get started with your board, you will only need to install a plugin, which is explained in the guide below:

• Getting started with the Web Editor

Arduino IoT Cloud

The Nano RP2040 Connect is compatible with the Arduino IoT Cloud, a cloud service that allows you to create IoT applications in just minutes.

If you need help to get started, you can go through the Nano RP2040 Connect with Arduino IoT Cloud tutorial.

Upgrading the Firmware

If you need to upgrade the firmware on your Nano RP2040 Connect, follow the link below to a detailed guide.

• Upgrading Nano RP2040 Connect NINA firmware

This guide is for updating the firmware on the NINA W-102 module (Wi-Fi).

Bootloader

Since our upload procedure relies on the Raspberry’s bootloader using a mass storage device, if your computer is fast enough during an upload, it can notify you about an USB removable being plugged.

When a sketch is uploaded successfully, the mass storage of the Nano RP2040 Connect may be visible in the operating system. The mass storage should only appear for a few seconds, then it will automatically close. When this occurs, we can force the ROM bootloader mode, which will enable mass storage, allowing us to upload UF2 images like CircuitPython / MicroPython or a regular Arduino sketch.

Forcing Bootloader

There is a risk that the uploading process gets stuck during an upload. If this happens, we can double-tap the reset button, to forcefully trigger the bootloader.

Board Not Detected

Sometimes the board is not detected even when the board is connected to your computer. This can be solved through the following steps:

1. Connect the board to your computer via USB.

2. Place a jumper wire between the REC and GND pins on the board, then press the reset button.

3. This will open the mass storage device. You can now remove the jumper wire.

4. Upload a basic sketch, such as the blink example to the board (even though it is not visible in the port selection).

5. When it has finished uploading, your board should be visible in the board/port selection, and your board's built-in LED should be blinking. This means it is successful!

Alternatively, you can choose to factory-reset the board by dragging the

blink.ino.elf.uf2

• Download the blink.ino.elf.uf2 file

After dragging the

U2F

red

green

blue

Pins

Analog Pins

The Nano RP2040 Connect has 8 analog pins, that can be used through the

analogRead()

Copy
1value = analogRead(pin, value);

Please note: pin

A4

and

A5

should be used for I2C only.

Please note: pin

A6

and

A7

does not support PWM.

PWM Pins

Most of the digital & analog pins can be used as PWM (Pulse Width Modulation) pins, the exception being the following pins:

• A4
• A5
• A6
• A7

Copy
1analogWrite(pin, value);

Digital Pins

There are a total of 14 digital pins, whereas the 8 analog pins can also be used as digital pins.

Please note: A4 and A5 are I2C only, while A6 and A7 can only be used as inputs.

To use them, we first need to define them inside the

void setup()

Note: digital pin 3 cannot be configured as

INPUT_PULLUP

.

Copy
1pinMode(pin, INPUT); //configured as an input
2pinMode(pin, OUTPUT); //configured as an output
3pinMode(pin, INPUT_PULLUP); //uses the internal 10k ohm resistor

To read the state of a digital pin:

Copy
1state = digitalRead(pin);

To write a state to a digital pin:

Copy
1digitalWrite(pin, HIGH);

5V Pin

The Arduino RP2040 Connect operates at 3.3 V, and has the 5V pin (VUSB) disabled by default. This is a safety precaution, as connecting higher voltage signals to the board can damage the hardware.

The 5V pin will be enabled if the pads marked VUSB are shorted, by soldering them.

The VUSB pin is located on the bottom of the board. The pads on the Arduino RP2040 Connect are highlighted below.

IMU

LSM6DSOXTR

The LSM6DSOXTR from STM is an IMU (Inertial Measurement Unit) that features a 3D digital accelerometer and a 3D digital gyroscope. It features among many other things, a machine learning core, which is useful for any motion detection projects, such as free fall, step detector, step counter, pedometer.

This module also features an embedded temperature sensor.

LSM6DSOX Library

To access the data from the LSM6DSOX module, we need to install the LSM6DSOX library, which comes with examples that can be used directly with the Nano RP2040 Connect.

It can be installed directly from the library manager through the IDE of your choice. To use it, we need to include at the top of the sketch:

Copy
1#include <Arduino_LSM6DSOX.h>

And to initialize the library, we can use the following command inside

void setup()

Copy
1if (!IMU.begin()) {
2    Serial.println("Failed to initialize IMU!");
3    while (1);
4  }

Accelerometer

The accelerometer data can be accessed through the following commands:

Copy
1float x, y, z;
2
3  if (IMU.accelerationAvailable()) {
4    IMU.readAcceleration(x, y, z);
5  }

Gyroscope

The gyroscope data can be accessed through the following commands:

Copy
1float x, y, z;
2
3  if (IMU.gyroscopeAvailable()) {
4    IMU.readGyroscope(x, y, z);
5  }

Temperature

The temperature data can be accessed through the following code:

Copy
1if (IMU.temperatureAvailable())
2  {
3    int temperature_deg = 0;
4    IMU.readTemperature(temperature_deg);
5
6    Serial.print("LSM6DSOX Temperature = ");
7    Serial.print(temperature_deg);
8    Serial.println(" °C");
9  }

Tutorials

If you want to learn more on how to use the IMU, please check out the tutorial below:

• Accessing IMU data with Nano RP2040 Connect
• Using the IMU Machine Learning Core Features

Microphone

MP34DT05

The MP34DT05 is a compact, low-power omnidirectional digital MEMS microphone with an IC interface. It has a 64 dB signal-to-noise ratio, is capable of sensing acoustic waves and can operate in temperatures of -40 °C to +85 °C.

PDM Library

To access the data from the MP34DT05, we need to use the PDM library that is included in the Arduino Mbed OS Nano Boards core. If the core is installed, you will find an example that works by browsing File > Examples > PDM > PDMSerialPlotter.

• Please note: The sampling frequency in the PDMSerialPlotter example is set to 16000 Hz. If the microphone appears to not be working (monitor is printing a value of -128), try to change this rate to 20000 Hz. You can change this at the top of the PDMSerialPlotter example sketch, as shown in the example below:

Copy
1static const int frequency = 20000; //frequency at 20 KHz instead of 16 KHz

Tutorials

If you want to learn more on how to use the Microphone, please check out the tutorial below:

• Reading microphone data with Nano RP2040 Connect

RGB

Please note: While using the Bluetooth® Low Energy mode on the NINA module, the RGB cannot be used by default. While the module is in Bluetooth® Low Energy mode, SPI is deactivated, which is used to control the RGBs.

The Nano RP2040 Connect features a built-in RGB that can be utilized as a feedback component for applications. The RGB is connected through the W-102 module, so the

WiFiNINA

The

WiFiNINA

Copy
1#include <WiFiNINA.h>

The pins needs to be defined inside

void setup()

Copy
1pinMode(LEDR, OUTPUT);
2pinMode(LEDG, OUTPUT);
3pinMode(LEDB, OUTPUT);

To turn ON the pixels, write a

HIGH

Copy
1digitalWrite(LEDR, HIGH); //RED
2digitalWrite(LEDG, HIGH); //GREEN
3digitalWrite(LEDB, HIGH); //BLUE

To turn OFF the pixels, write a

LOW

Copy
1digitalWrite(LEDR, LOW); //RED
2digitalWrite(LEDG, LOW); //GREEN
3digitalWrite(LEDB, LOW); //BLUE

We can also choose a value between 255 - 0 to write to the LED:

Copy
1analogWrite(LEDR, 72);  //GREEN 
2analogWrite(LEDG, 122); //BLUE 
3analogWrite(LEDB, 234); //RED

Communication

Like other Arduino® products, the Nano RP2040 Connect features dedicated pins for different protocols.

SPI

The pins used for SPI (Serial Peripheral Interface) on the Nano RP2040 Connect are the following:

• (CIPO) - D12
• (COPI) - D11
• (SCK) - D13
• (CS) - Any GPIO (except for A6/A7)

The signal names MOSI, MISO and SS has been replaced by COPI (Controller Out, Peripheral In), CIPO (Controller In, Peripheral Out) and CS (Chip Select).

To use SPI, we first need to include the SPI library.

Copy
1#include <SPI.h>

Inside

void setup()

Copy
1SPI.begin();

And to write to the device:

Copy
1digitalWrite(chipSelectPin, LOW); //pull down the CS pin
2  
3  SPI.transfer(address); // address for device, for example 0x00
4  SPI.transfer(value); // value to write
5
6  digitalWrite(chipSelectPin, HIGH); // pull up the CS pin

I2C

The pins used for I2C (Inter-Integrated Circuit) on the Nano RP2040 Connect are the following:

• (SDA) - A4
• (SCL) - A5

To use I2C, we can use the Wire library, which we need to include at the top of our sketch.

Copy
1#include <Wire.h>

Inside

void setup()

Copy
1Wire.begin();

And to write something to a device connected via I2C, we can use the following commands:

Copy
1Wire.beginTransmission(1); //begin transmit to device 1
2  Wire.write(byte(0x00)); //send instruction byte 
3  Wire.write(val); //send a value
4  Wire.endTransmission(); //stop transmit

UART

The pins used for UART (Universal asynchronous receiver-transmitter) are the following:

• (Rx) - D0
• (Tx) - D1

To send and receive data through UART, we will first need to set the baud rate inside

void setup()

Copy
1Serial1.begin(9600);

To read incoming data, we can use a while loop() to read each individual character and add it to a string.

Copy
1while(Serial1.available()){
2    delay(2);
3    char c = Serial1.read();
4    incoming += c;
5  }

And to write something, we can use the following command:

Copy
1Serial1.write("Hello world!");

Connectivity

The Nano RP2040 Connect supports both Wi-Fi and Bluetooth® through the uBlox W-102 module. To use this module, we can use the WiFiNINA library or the ArduinoBLE library.

Wi-Fi

To use the Wi-Fi module on the Nano RP2040 Connect, we will need to install the WiFiNINA library, and include it at the top of our sketch:

Copy
1#include <WiFiNINA.h>

To connect to a Wi-Fi network, we can use the following command:

Copy
1WiFi.begin(ssid, pass);

GET / POST Requests

The WiFiNINA library can be used to make GET & POST requests, while connected to the server. The command below is used to connect to

www.google.com

arduino

Copy
1if (client.connect(server, port)) {
2    client.println("GET /search?q=arduino HTTP/1.1");
3    client.println("Host: www.google.com");
4    client.println("Connection: close");
5    client.println();
6  }

Tutorials

• Web Server AP mode with Arduino Nano RP2040 Connect
• RGB Control over Wi-Fi with Arduino Nano RP2040 Connect

Bluetooth®

Please note: While using the Bluetooth® Low Energy mode on the NINA module, the RGB cannot be used by default. While the module is in Bluetooth® Low Energy mode, SPI is deactivated, which is used to control the RGBs.

To enable Bluetooth® on the Nano RP2040 Connect, we can use the ArduinoBLE library, and include it at the top of our sketch:

Copy
1#include <ArduinoBLE.h>

Set the service and characteristic:

Copy
1BLEService ledService("180A"); // BLE LED Service
2BLEByteCharacteristic switchCharacteristic("2A57", BLERead | BLEWrite);

Set advertised name and service:

Copy
1BLE.setLocalName("Nano RP2040 Connect");
2  BLE.setAdvertisedService(ledService);

Start advertising:

Copy
1BLE.advertise();

Listen for BLE peripherals to connect:

Copy
1BLEDevice central = BLE.central();

Tutorials

• Nano RP2040 device to device via Bluetooth®

USB Keyboard

To use the board as a keyboard, you can refer to the USBHID library that can be found inside the core.

You first need to include the libraries and create an object:

Copy
1#include "PluggableUSBHID.h"
2#include "USBKeyboard.h"
3
4USBKeyboard Keyboard;

Then use the following command to write something:

Copy
1Keyboard.printf("This is RP2040 speaking!");