Adafruit ItsyBitsy M4 Express featuring ATSAMD51

Compact ATSAMD51 Cortex-M4 board running at 120 MHz with 512KB Flash and 192KB RAM in the ItsyBitsy footprint. Significant performance step up from M0-class ItsyBitsy boards in the same small form factor.

Logical pinout · physical placement not verified

BAT
Type · Power
G
Type · Ground
USB
Type · USB
13
Type · Signal
12
Type · Signal
11
Type · Signal
10
Type · Signal
9
Type · Signal
7
Type · Signal
5
Type · Signal
SCL
Type · I2C
SDA
Type · I2C
TX
Type · UART
RX
Type · UART
3
Type · Signal
4
Type · Signal
RST
Type · Control
3V
Type · Power
AREF
Type · Analog
VHI
Type · Power
A0
Type · Analog
A1
Type · Analog
A2
Type · Analog
A3
Type · Analog
A4
Type · Analog
A5
Type · Analog
SCK
Type · SPI
MO
Type · Signal
MI
Type · Signal
2
Type · Signal
En
Type · Control

Pin	Type
BAT	Power
G	Ground
USB	USB
13	Signal
12	Signal
11	Signal
10	Signal
9	Signal
7	Signal
5	Signal
SCL	I2C
SDA	I2C
TX	UART
RX	UART
3	Signal
4	Signal
RST	Control
3V	Power
AREF	Analog
VHI	Power
A0	Analog
A1	Analog
A2	Analog
A3	Analog
A4	Analog
A5	Analog
SCK	SPI
MO	Signal
MI	Signal
2	Signal
En	Control

Logical pinout · physical placement not verified

Pin details

31 connections

BAT
Power
G
Ground
USB
USB
13
Signal
12
Signal
11
Signal
10
Signal
9
Signal
7
Signal
5
Signal
SCL
I2C
SDA
I2C
TX
UART
RX
UART
3
Signal
4
Signal
RST
Control
3V
Power
AREF
Analog
VHI
Power
A0
Analog
A1
Analog
A2
Analog
A3
Analog
A4
Analog
A5
Analog
SCK
SPI
MO
Signal
MI
Signal
2
Signal
En
Control

Start wiring

USB · 3.3 V

Confirm the data interface matches your host board.

Module pins: BAT, USB, 3V, VHI, G, 13, 12, 11. Schematik maps them to your board in the app.

Other MCUs

228 other options

Specialists: Teensy for high-clock audio and USB, Adafruit SAMD boards running CircuitPython or the Arduino IDE, proper STM32 eval kits, and the micro:bit classroom ecosystem. Schematik builds target ESP32, Arduino Uno, and Pico; come here when you have a specific reason to.

View all 228

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Pinout