Adafruit QT Py - SAMD21 Dev Board with STEMMA QT
Pinout
- 3V
Regulated 3.3 V output from the onboard regulator; Adafruit Learn says it can supply about 500 mA.
Type · PowerVoltage · 3.3V regulated output - 5V
5 V from the USB port; can be used as a voltage input only with a diode as described by Adafruit Learn.
Type · PowerVoltage · 5V USB rail - GND
Power, data, and signal ground.
Type · GroundVoltage · 0V - D0A0
Digital/analogue GPIO 0; true 10-bit analogue output and capacitive touch input; no PWM.
Type · GPIO, AnalogVoltage · 3.3V logic - D1A1
Digital/analogue GPIO 1; capacitive touch input or AREF pin.
Type · GPIO, AnalogVoltage · 3.3V logic - D2A2
Digital/analogue GPIO 2; PWM-capable and capacitive touch input.
Type · GPIO, AnalogVoltage · 3.3V logic - D3A3
Digital/analogue GPIO 3; PWM-capable and capacitive touch input.
Type · GPIO, AnalogVoltage · 3.3V logic - D4SDA
I2C data and digital pin 4; PWM-capable, no analogue input. STEMMA QT uses this SDA signal.
Type · GPIO, I2CVoltage · 3.3V logic - D5SCL
I2C clock and digital pin 5; PWM-capable, no analogue input. STEMMA QT uses this SCL signal.
Type · GPIO, I2CVoltage · 3.3V logic - D6TXA6
Serial1 transmit output; also analogue/digital GPIO 6, PWM-capable and capacitive touch input.
Type · GPIO, Analog, UARTVoltage · 3.3V logic - D7RXA7
Serial1 receive input; also analogue/digital GPIO 7, PWM-capable and capacitive touch input.
Type · GPIO, Analog, UARTVoltage · 3.3V logic - D8SCKA8
Hardware SPI clock; also analogue/digital GPIO 8 and PWM-capable output.
Type · GPIO, Analog, SPIVoltage · 3.3V logic - D9MIA9
Hardware SPI MISO, microcontroller-in serial-out; also analogue/digital GPIO 9 and PWM-capable output.
Type · GPIO, Analog, SPIVoltage · 3.3V logic - D10MOA10
Hardware SPI MOSI, microcontroller-out serial-in; also analogue/digital GPIO 10 and PWM-capable output.
Type · GPIO, Analog, SPIVoltage · 3.3V logic - D11NeoPixel
Onboard NeoPixel signal pin, connected to digital pin 11.
Type · GPIOVoltage · 3.3V logic - D12NeoPixel power
Onboard NeoPixel power control; Adafruit Learn says set pin 12 low to turn off the pixel for low power usage.
Type · GPIOVoltage · 3.3V logic - STEMMA QT
Plug-and-play I2C connector using the board SCL and SDA signals for STEMMA QT/Qwiic accessories.
Type · UnknownVoltage · 3.3V I2C connector
| Pin | Type | Function | Voltage |
|---|---|---|---|
| 3V | Power | Regulated 3.3 V output from the onboard regulator; Adafruit Learn says it can supply about 500 mA. | 3.3V regulated output |
| 5V | Power | 5 V from the USB port; can be used as a voltage input only with a diode as described by Adafruit Learn. | 5V USB rail |
| GND | Ground | Power, data, and signal ground. | 0V |
| D0A0 | GPIO, Analog | Digital/analogue GPIO 0; true 10-bit analogue output and capacitive touch input; no PWM. | 3.3V logic |
| D1A1 | GPIO, Analog | Digital/analogue GPIO 1; capacitive touch input or AREF pin. | 3.3V logic |
| D2A2 | GPIO, Analog | Digital/analogue GPIO 2; PWM-capable and capacitive touch input. | 3.3V logic |
| D3A3 | GPIO, Analog | Digital/analogue GPIO 3; PWM-capable and capacitive touch input. | 3.3V logic |
| D4SDA | GPIO, I2C | I2C data and digital pin 4; PWM-capable, no analogue input. STEMMA QT uses this SDA signal. | 3.3V logic |
| D5SCL | GPIO, I2C | I2C clock and digital pin 5; PWM-capable, no analogue input. STEMMA QT uses this SCL signal. | 3.3V logic |
| D6TXA6 | GPIO, Analog, UART | Serial1 transmit output; also analogue/digital GPIO 6, PWM-capable and capacitive touch input. | 3.3V logic |
| D7RXA7 | GPIO, Analog, UART | Serial1 receive input; also analogue/digital GPIO 7, PWM-capable and capacitive touch input. | 3.3V logic |
| D8SCKA8 | GPIO, Analog, SPI | Hardware SPI clock; also analogue/digital GPIO 8 and PWM-capable output. | 3.3V logic |
| D9MIA9 | GPIO, Analog, SPI | Hardware SPI MISO, microcontroller-in serial-out; also analogue/digital GPIO 9 and PWM-capable output. | 3.3V logic |
| D10MOA10 | GPIO, Analog, SPI | Hardware SPI MOSI, microcontroller-out serial-in; also analogue/digital GPIO 10 and PWM-capable output. | 3.3V logic |
| D11NeoPixel | GPIO | Onboard NeoPixel signal pin, connected to digital pin 11. | 3.3V logic |
| D12NeoPixel power | GPIO | Onboard NeoPixel power control; Adafruit Learn says set pin 12 low to turn off the pixel for low power usage. | 3.3V logic |
| STEMMA QT | Unknown | Plug-and-play I2C connector using the board SCL and SDA signals for STEMMA QT/Qwiic accessories. | 3.3V I2C connector |
Pin details
17 connections- 3V
Regulated 3.3 V output from the onboard regulator; Adafruit Learn says it can supply about 500 mA.
PowerVoltage · 3.3V regulated output - 5V
5 V from the USB port; can be used as a voltage input only with a diode as described by Adafruit Learn.
PowerVoltage · 5V USB rail - GND
Power, data, and signal ground.
GroundVoltage · 0V - D0A0
Digital/analogue GPIO 0; true 10-bit analogue output and capacitive touch input; no PWM.
GPIO, AnalogVoltage · 3.3V logic - D1A1
Digital/analogue GPIO 1; capacitive touch input or AREF pin.
GPIO, AnalogVoltage · 3.3V logic - D2A2
Digital/analogue GPIO 2; PWM-capable and capacitive touch input.
GPIO, AnalogVoltage · 3.3V logic - D3A3
Digital/analogue GPIO 3; PWM-capable and capacitive touch input.
GPIO, AnalogVoltage · 3.3V logic - D4SDA
I2C data and digital pin 4; PWM-capable, no analogue input. STEMMA QT uses this SDA signal.
GPIO, I2CVoltage · 3.3V logic - D5SCL
I2C clock and digital pin 5; PWM-capable, no analogue input. STEMMA QT uses this SCL signal.
GPIO, I2CVoltage · 3.3V logic - D6TXA6
Serial1 transmit output; also analogue/digital GPIO 6, PWM-capable and capacitive touch input.
GPIO, Analog, UARTVoltage · 3.3V logic - D7RXA7
Serial1 receive input; also analogue/digital GPIO 7, PWM-capable and capacitive touch input.
GPIO, Analog, UARTVoltage · 3.3V logic - D8SCKA8
Hardware SPI clock; also analogue/digital GPIO 8 and PWM-capable output.
GPIO, Analog, SPIVoltage · 3.3V logic - D9MIA9
Hardware SPI MISO, microcontroller-in serial-out; also analogue/digital GPIO 9 and PWM-capable output.
GPIO, Analog, SPIVoltage · 3.3V logic - D10MOA10
Hardware SPI MOSI, microcontroller-out serial-in; also analogue/digital GPIO 10 and PWM-capable output.
GPIO, Analog, SPIVoltage · 3.3V logic - D11NeoPixel
Onboard NeoPixel signal pin, connected to digital pin 11.
GPIOVoltage · 3.3V logic - D12NeoPixel power
Onboard NeoPixel power control; Adafruit Learn says set pin 12 low to turn off the pixel for low power usage.
GPIOVoltage · 3.3V logic - STEMMA QT
Plug-and-play I2C connector using the board SCL and SDA signals for STEMMA QT/Qwiic accessories.
UnknownVoltage · 3.3V I2C connector
Start wiring
USB · 3.3 V
Confirm the data interface matches your host board.
Module pins: 3V, 5V, GND, A0 / D0, A1 / D1, A2 / D2, A3 / D3, SDA / D4. Schematik maps them to your board in the app.
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