The already large family of Arduino boards is enriched with a new entry, the Arduino Nano RP2040 Connect, which integrates the Raspberry Pi Foundation’s RP2040 microcontroller with the u-blox NINA-W102 Wi-Fi and Bluetooth radio module, as well as a rich set of advanced sensors capable of supporting algorithm Artificial intelligence. In fact, the board includes a digital microphone that supports voice-activated features, a 6-axis inertial motion (IMU) sensor, a mini RGB LED, and a wide availability of flash memory (16MB) capable of meeting even the most demanding applications. The new Raspberry Pi RP2040 board inherits programming support for MicroPython and the C/C++ language, both of which are based on the SDKs developed for the Raspberry Pi Pico board. Like all other boards in the Arduino family, the latest addition supports native programming environments, such as the well-known Arduino IDE (now in version 2.0), Arduino CLI, IoT Cloud, and Web Editor. The latter allows programming and controlling the operation of the Nano RP2040 Connect directly from a web browser. Thus, it is possible to upload drawings over the air using an instant remote control from the free Arduino IoT Remote smartphone app. The RP2040 microcontroller was chosen because it represents the “union characteristic” between the Raspberry and Arduino worlds, and is the ideal solution for all those applications that do not require the complexity and performance of a “complete” Raspberry Pi, while making use of advanced features at a very competitive cost. Another noteworthy feature is the board’s affiliation with the Arduino Nano Mbed OS family, a group of boards with a common small form factor (“Nano” imprint, only 18 x 43 mm in size) and support for IoT applications based on the ARM Mbed OS operating system. Currently, this family includes three boards: Nano 33 BLE, Nano 33 BLE Sense and Nano RP2040 Connect (Nano 33 IoT is not part of it, as it does not support Mbed OS). Figure 1 shows a three-quarter view of the Arduino Nano RP2040 Connect board, here in the version without the pin headers installed. Figure 1: Arduino Nano RP2040 block diagram The board block diagram is shown in Figure 2. The core is represented by the RP2040 microcontroller, capable of communicating with the host development environment and debugging via classic USB connectivity and with an external 16MB flash memory via a Quad-SPI high-speed serial interface . The 3.3-V power supply is provided by the MP2322 regulator, with an input source that can be selected from a USB port (VUSB) or from an external power source (VIN). The NINA W102 Wi-Fi/Bluetooth module is connected to the micro via I2C, SPI and UART interfaces, and an RGB LED is connected to it. For other sensors, the MEMS microphone is connected to the micro via the Pulse Density Modulation (PDM) digital audio interface, while the 6-axis motion sensor and authentication module are connected via the I2C bus. An external MEMS oscillator operating at a frequency of 12MHz provides the clock pulse. Figure 2: Board Block Diagram Components The main components of the board are highlighted in Figure 3. First, we have the RP2040 chip, a 32-bit dual-core microcontroller based on an ARM Cortex M0+ and operating at 133MHz, accompanied by an integrated 264KB SRAM. The excellent performance and high efficiency of this central console allow it to support machine learning algorithms developed using TinyML, TensorFlow Lite or Edge Impulse. In addition to full support for MicroPython (available starting July 2021), the board comes with a free OpenMV license for machine vision projects. Features offered by the RP2040 microcontroller include: Direct memory access controller, USB 1.1 and PHY controller, with host and device support. Eight programmable IO IO state machines to support extended peripherals 4-channel ADC with internal temperature sensor, 0.5-MS /s, 12-bit switchable SWD debugging, two on-chip PLLs for USB generation and a base clock, multiple low-power mode support USB host/device support 1.1 internal voltage regulator for basic voltage supply high-performance bus/advanced terminal bus Figure 3: Main board components After the MCU, this card’s second strong point is certainly connectivity, made possible by the u-blox NINA W102 radio unit, an inexpensive and easily adaptable device. The module also adds four analog GPIOs (the RP2040 has only four analog pins), bringing the total to eight, in line with other Arduino Nano boards. The radio unit, equipped with a built-in antenna, is based on a dual-core Xtensa LX6 CPU, which in turn can be programmed independently of the RP2040 using the SWD interface and special pads located on the back of the board. In practice, the NINA W102 uses the same CPU as the ESP32, and is one of the most popular hardware platforms for makers, along with the Arduino and Raspberry Pi. The RGB LED is connected to the radio module and can be powered using the same library (WiFiNINA) developed for the module itself. The connection used in IoT applications requires a high degree of security in order to maintain the consistency of transmitted data in all operating conditions and to prevent possible attacks from the outside. For this purpose, the designers have included a powerful encoder, the Microchip ATECC608A already used in the Arduino MKR family boards. The encrypted coprocessor, which has a particularly low power consumption, provides secure boot support, hardware support for asymmetric signaling, validation, and key agreement, hardware support for symmetric algorithms (SHA-256 and HMAC, AES-128), and networking and key management support. The sensor equipment includes a six-axis ST LSM6DSOX IMU, which combines a 3D accelerometer and a 3D gyroscope with a dedicated machine learning core. The component primarily intended for the mobile market, where the “always” operation requires particularly low power consumption, offers the following technical characteristics: 3D gyroscope, ±2-/±4-/±8-/±16 g full-scale accelerometer 3D, ±125-/±250-/±500-/±1,000-/±2,000-dps Advanced Full Gauge, Step Detector, and Pedometer, Significant Motion Detection, Tilt Detection Standard Interrupts: Free Fall, Alarm , 6D/4D steering, tap and double-click Programmable limited state machine: accelerometer, gyroscope, and basic external sensors for machine learning Built-in temperature sensor The device can be easily programmed using the custom Arduino LSM6DSOX library. Another related sensor is the omnidirectional digital microphone, which can be used for voice activation, voice control, and even AI voice recognition. The MP34DT05 microphone captures and analyzes audio in real time and can be used to create an audio interface for any project. The ST MP34DT05-A is an ultra-compact, low-power, omnidirectional digital MEMS microphone designed with a capacitive sensing element and IC interface. The sensing element, capable of detecting sound waves, is manufactured using the MEMS process, while the interface IC is manufactured using a CMOS process that provides a digital signal externally in PDM format. The MP34DT05-A is a low-distortion digital microphone with a signal-to-noise ratio of 64 dB and a sensitivity of -26-dBFS ± 3-dB. The device can be programmed using the custom Arduino PDM library. In terms of programmable I/O pins, the board provides eight analog input pins and 22 digital I/O ports (20 of which can be configured as PWM generators or as an external interrupt). An integrated LED is also available to the user at Pin 13. Figure 4 shows the complete pinout of the Arduino Nano RP2040 Connect Board, which is also available with header pins pre-installed. The pin layout is well organized, with all the power and analog pins on the left header and the digital pins on the right side. As shown in Figure 2, the RP2040 MCU provides support for UART, SPI, and I2C connections. Figure 4: Board Pin In terms of applications, the Arduino Nano RP2040 Connect can be adapted to a wide range of use cases, including: Edge computing: TinyML can be used for anomaly detection, cough detection, gesture analysis, and more. Wearables: Reduced space allows machine learning algorithms to be deployed on a wide range of wearable devices, including sports trackers and virtual reality consoles. Voice Assistant: The Arduino Nano RP2040 Connect includes an omnidirectional microphone that can be used as a personal digital assistant, enabling voice control of various projects. .