# Arduino UNO R4 WiFi

> Prototype controls, sensors and small connected displays.

- **Category:** Boards & controllers
- **Availability:** Listed by maker
- **Price:** US$27.50 (at store-usa.arduino.cc), checked 2026-09-15
- **Good for:** Prototype controls, sensors and small connected displays.
- **You'll need:** USB data cable, Arduino tools and voltage-compatible components.
- **Trade-off:** UNO R4 firmware and libraries are not universally interchangeable with UNO R3.
- **Page:** https://gadgets.sh/devices/arduino-uno-r4-wifi/

## Where to buy

| Shop | Status | Link |
|---|---|---|
| Arduino | Orderable | https://store.arduino.cc/products/uno-r4-wifi?utm_source=gadgets.sh&utm_medium=referral&utm_campaign=arduino-uno-r4-wifi&utm_content=api |
| Arduino US | Orderable | https://store-usa.arduino.cc/products/uno-r4-wifi?utm_source=gadgets.sh&utm_medium=referral&utm_campaign=arduino-uno-r4-wifi&utm_content=api |
| Amazon | Orderable | https://www.amazon.com/dp/B0C8V88Z9D?utm_source=gadgets.sh&utm_medium=referral&utm_campaign=arduino-uno-r4-wifi&utm_content=api |
| DFRobot | Orderable | https://www.dfrobot.com/product-2700.html?utm_source=gadgets.sh&utm_medium=referral&utm_campaign=arduino-uno-r4-wifi&utm_content=api |
| Seeed Studio | Orderable | https://www.seeedstudio.com/Arduino-Uno-Rev4-WiFi-p-5717.html?utm_source=gadgets.sh&utm_medium=referral&utm_campaign=arduino-uno-r4-wifi&utm_content=api |
| Arduino | Documentation at docs.arduino.cc | https://docs.arduino.cc/hardware/uno-r4-wifi/?utm_source=gadgets.sh&utm_medium=referral&utm_campaign=arduino-uno-r4-wifi&utm_content=api |

## Blueprint

**Schematics published.** Arduino publishes an official schematic PDF, full pinout PDF and datasheet PDF for the board; no editable Eagle/KiCad source files were found.

### Design files

- schematic: [UNO R4 WiFi schematics (PDF)](https://docs.arduino.cc/resources/schematics/ABX00087-schematics.pdf) (PDF)
- pinout: [UNO R4 WiFi full pinout (PDF)](https://docs.arduino.cc/resources/pinouts/ABX00087-full-pinout.pdf) (PDF)
- datasheet: [UNO R4 WiFi board datasheet (PDF)](https://docs.arduino.cc/resources/datasheets/ABX00087-datasheet.pdf) (PDF)

### Key parts

| Part | Role | Datasheet |
|---|---|---|
| Renesas RA4M1 (R7FA4M1AB), Cortex-M4, 48 MHz | main MCU | https://www.renesas.com/en/products/ra4m1 |
| ESP32-S3-MINI-1-N8 | Wi-Fi/BLE co-processor module | https://www.espressif.com/sites/default/files/documentation/esp32-s3-mini-1_esp32-s3-mini-1u_datasheet_en.pdf |

_Notes:_ All three docs.arduino.cc PDFs returned HTTP 200. No arduino/* GitHub repo with Eagle/KiCad source for this specific board was found (searched GitHub for ABX00087 and "uno r4" eagle/kicad — no hits), so classified as schematics-only rather than open-hardware.

## Specifications

### Processors & display

| | |
|---|---|
| Main MCU | Renesas RA4M1 Cortex-M4F, 48 MHz |
| Main memory | 256 KB flash, 32 KB SRAM, 8 KB data EEPROM |
| Wireless MCU | ESP32-S3-MINI-1-N8; separate 3.3 V processor |
| Wireless | 2.4 GHz 802.11b/g/n and Bluetooth 5 LE |
| Bluetooth software | UNO R4 WiFi is on Arduino’s supported BLE list; no Classic support claim |
| Display | 12 × 8 red LED matrix |

### Pins & power

| | |
|---|---|
| I/O | 14 digital pins and six analog inputs |
| Logic levels | Main headers: 5 V; ESP header and Qwiic: 3.3 V only |
| GPIO current | 8 mA maximum per RA4M1 GPIO; power motors separately |
| I²C | Wire on A4/A5; Wire1 on the 3.3 V Qwiic connector |
| SPI / UART | SPI on D10–D13 or ICSP; UART on D0/D1 |
| CAN connection | D13 receive / D10 transmit; external transceiver required |
| ADC / DAC | Up to 14-bit ADC; 12-bit DAC on A0 |
| Supply input | USB-C: 5 V; VIN/barrel jack: 6–24 V |

### Setup & recovery

| | |
|---|---|
| IDE setup | Install Arduino IDE 2 and the UNO R4 board package; select WiFi model |
| Programming cable | USB-C data cable; board registration is optional |
| Connectivity firmware | IDE 2.2.1+ has Tools → Firmware Updater for the ESP32-S3 bridge |
| After updating | Updater overwrites the sketch; unplug/reconnect before uploading again |
| Bridge recovery | Use the board-specific espflash recovery if USB identification is lost |
| Library migration | Check the UNO R4 compatibility list before reusing AVR code or shields |
| Hardware files | Published pinout, schematic, CAD and STEP downloads |

## Documentation

- [UNO R4 WiFi overview and CAD downloads](https://docs.arduino.cc/hardware/uno-r4-wifi/)
- [UNO R4 WiFi user manual / datasheet](https://docs.arduino.cc/resources/datasheets/ABX00087-datasheet.pdf)
- [UNO R4 WiFi full pinout](https://docs.arduino.cc/resources/pinouts/ABX00087-full-pinout.pdf)
- [UNO R4 WiFi schematics](https://docs.arduino.cc/resources/schematics/ABX00087-schematics.pdf)
- [Arduino-authored UNO R4 WiFi CAN wiring guide](https://docs.arduino.cc/tutorials/uno-r4-wifi/can/)
- [Arduino-authored IDE and board-package setup](https://docs.arduino.cc/tutorials/uno-r4-wifi/r4-wifi-getting-started/)
- [Connectivity firmware update and reconnect requirement](https://support.arduino.cc/hc/en-us/articles/9670986058780-Update-the-connectivity-module-firmware-on-UNO-R4-WiFi)
- [ESP32-S3 USB bridge recovery](https://support.arduino.cc/hc/en-us/articles/16379769332892-Restore-the-USB-connectivity-firmware-on-UNO-R4-WiFi-with-espflash)
- [UNO R4 library compatibility list](https://github.com/arduino/uno-r4-library-compatibility)
- [Arduino-supported wireless connectivity](https://support.arduino.cc/hc/en-us/articles/4407129094546-Boards-and-shields-with-wireless-connectivity)

---
Source: gadgets.sh · https://gadgets.sh/devices/arduino-uno-r4-wifi/ · JSON: https://gadgets.sh/api/v1/devices/arduino-uno-r4-wifi.json