The Nano R4 merges for 's signature ease of use with the powerful RA4M1 microcontroller, making it effortless to scale on the R4 to production-ready applications. Compact and versatile, the Nano R4 maintains the same pinout as other boards in the Nano family and features ribbon pins for easy hardware integration, an on-board Qwiic connector for quick sensor and peripheral expansion, and a programmable RGB LED for intuitive system feedback. Easy transition from prototyping to production: Leverages the already trusted RA4M1 microcontroller of the R4 family, requiring minimal code adjustments. Compact, production-ready design: The tiny 4.3 x 1.7 cm footprint, castellated pins, and single-sided assembly facilitate easy integration into custom hardware. Easy expandability: The built-in Qwiic connector and additional 5V port allow seamless connection to a wide range of sensors and actuators, including Modulino nodes. Customizable feedback: Use programmable RGB to indicate system status for faster debugging and smarter user interaction. Flexible, familiar platform: Enjoy for 's rich ecosystem, intuitive development environment, and strong community support. USB USB-C programming port Pins: 21 digital I/O pins (all exposed I/O can be used as digital I/O pins) Analog input pins: 8 : 1 PWM pins: 6 External interrupts: 2, 3 : A0 OPAMP: A1, A2, A3 VRTC: J5 Communication: UART: 1 : 2 (5V: A4, A5 / 3.3V: Qwiic, J3, J4) SPI: 1 Power: 1 Power: +5 Input voltage (VIN): +6-21 DC current: 8 mA Clock speed: Main core: 48 MHz Memory: RA4M1: Flash: 256 KB RAM: 32 KB EEPROM: 8 KB Aspect: Width: 18 mm Length: 45 mm Color: As Shown Material: PCB Package Contents: 1 * Development Board Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.