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Microcontroller · Development Board
Seeed Studio XIAO RP2350
XIAO-format RP2350 with dual Cortex-M33 or Hazard3 RISC-V cores and 19 GPIO.
- GPIO
- I2C
- SPI
- UART
- ADC
- PWM
- USB
- Processor
- Raspberry Pi RP2350A
- Logic
- 3.3 V GPIOTreat as not 5 V tolerant
- Power
- USB-C, battery pads, 5 V/3.3 V pins
- Format
- Tiny castellated module (21 x 17.8 mm)
Before you wire
3 cautions- 3.3 V GPIO.
- D4/D5 are I2C1. The arduino-pico Wire object defaults to I2C0 on back pads D13/D14 (GPIO17/16); use Wire1 for the edge pads.
- GPIO25 drives the user LED and GPIO22 the RGB LED; GPIO29 and GPIO19 are reserved for battery sensing.
Pin map
Connector
XIAO 14 castellated pads
USB-C at top, component side up, 7 pads down each long edge
Simplified technical illustration. Pin data is source-backed; verify against the linked documentation before wiring.
Pin
Hover, tap, or arrow to a pad to inspect it.
- USB-C at top, component side up; labels follow Seeed's XIAO RP2350 pin map, cross-checked with the arduino-pico variant and Zephyr.
- D labels are board labels, not raw RP2350 GPIO numbers; aliases give the GPIO.
- Back-side pads D11-D18 (UART1, I2C0, SPI1) are not shown on this 14-pad map.
All 14 pins (table)
| # | Signal | Role | Net | Also / notes |
|---|---|---|---|---|
| 1 | ADC | GPIO26 / ADC0 | ||
| 2 | ADC | GPIO27 / ADC1 | ||
| 3 | ADC | GPIO28 / ADC2 | ||
| 4 | SPI | SPI0 | GPIO5 / SPI0 CSn | |
| 5 | I2C | I2C1 | GPIO6 · I2C1. Arduino Wire defaults to I2C0 on back pads D13/D14; use Wire1 here. | |
| 6 | I2C | I2C1 | GPIO7 · I2C1. Arduino Wire defaults to I2C0 on back pads D13/D14; use Wire1 here. | |
| 7 | UART | UART0 | GPIO0 / UART0 TX | |
| 14 | Power | 5V | ||
| 13 | Ground | GND | ||
| 12 | Power | 3V3 | ||
| 11 | SPI | SPI0 | GPIO3 / SPI0 TX | |
| 10 | SPI | SPI0 | GPIO4 / SPI0 RX | |
| 9 | SPI | SPI0 | GPIO2 / SPI0 SCK | |
| 8 | UART | UART0 | GPIO1 / UART0 RX |
Revision notes
- USB-C at top, component side up; labels follow Seeed's XIAO RP2350 pin map, cross-checked with the arduino-pico variant and Zephyr.
Source references
Why it matters
- RP2350A can boot either its Arm Cortex-M33 or its Hazard3 RISC-V cores.
- Three analog inputs on the edge pads; a fourth ADC channel (GPIO29) reads the battery.
- Extra back pads add UART1, I2C0, and SPI1 for 19 GPIO in total.
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