Adafruit Bluefruit LE Shield - Bluetooth LE for Arduino
Arduino shield that adds Bluetooth Low Energy via a Nordic nRF51822-based module, interfacing over SPI at 4 MHz (5 pins: MISO, MOSI, SCK, CS on D8, IRQ on D7, RST on D4). Uses AT command set and supports GATT customization and OTA firmware updates.
Pinout
- 5VArduino shield power header
Module supply input, regulated down to 3.3V
Type · PowerVoltage · 3.3-5V input - GNDArduino shield power header
Common ground for power and logic
Type · GroundVoltage · 0V - SCK2x3 ICSP header
SPI clock, default connected to 2x3 ICSP SCK
Type · SPIVoltage · Arduino logic - MISO2x3 ICSP header
SPI MISO, nRF51 to Arduino
Type · SPIVoltage · Arduino logic - MOSI2x3 ICSP header
SPI MOSI, Arduino to nRF51
Type · SPIVoltage · Arduino logic - CSArduino digital header D8
SPI chip select, default digital 8
Type · SPIVoltage · Arduino logic - IRQArduino digital header D7
nRF51 interrupt to Arduino, default digital 7
Type · SignalVoltage · Arduino logic - RSTArduino digital header D4
Bluefruit module reset, default digital 4
Type · ControlVoltage · Arduino logic - SWCLKSWD pad
SWD clock for advanced/debug use
Type · UnknownVoltage · 3V logic - SWDIOSWD pad
SWD data for advanced/debug use
Type · UnknownVoltage · 3V logic - F.RSTfactory reset pad
Factory reset pad, tie to ground while powering up
Type · Control
| Pin | Position | Type | Function | Voltage |
|---|---|---|---|---|
| 5V | Arduino shield power header | Power | Module supply input, regulated down to 3.3V | 3.3-5V input |
| GND | Arduino shield power header | Ground | Common ground for power and logic | 0V |
| SCK | 2x3 ICSP header | SPI | SPI clock, default connected to 2x3 ICSP SCK | Arduino logic |
| MISO | 2x3 ICSP header | SPI | SPI MISO, nRF51 to Arduino | Arduino logic |
| MOSI | 2x3 ICSP header | SPI | SPI MOSI, Arduino to nRF51 | Arduino logic |
| CS | Arduino digital header D8 | SPI | SPI chip select, default digital 8 | Arduino logic |
| IRQ | Arduino digital header D7 | Signal | nRF51 interrupt to Arduino, default digital 7 | Arduino logic |
| RST | Arduino digital header D4 | Control | Bluefruit module reset, default digital 4 | Arduino logic |
| SWCLK | SWD pad | Unknown | SWD clock for advanced/debug use | 3V logic |
| SWDIO | SWD pad | Unknown | SWD data for advanced/debug use | 3V logic |
| F.RST | factory reset pad | Control | Factory reset pad, tie to ground while powering up |
Pin details
11 connections- 5VArduino shield power header
Module supply input, regulated down to 3.3V
PowerVoltage · 3.3-5V input - GNDArduino shield power header
Common ground for power and logic
GroundVoltage · 0V - SCK2x3 ICSP header
SPI clock, default connected to 2x3 ICSP SCK
SPIVoltage · Arduino logic - MISO2x3 ICSP header
SPI MISO, nRF51 to Arduino
SPIVoltage · Arduino logic - MOSI2x3 ICSP header
SPI MOSI, Arduino to nRF51
SPIVoltage · Arduino logic - CSArduino digital header D8
SPI chip select, default digital 8
SPIVoltage · Arduino logic - IRQArduino digital header D7
nRF51 interrupt to Arduino, default digital 7
SignalVoltage · Arduino logic - RSTArduino digital header D4
Bluefruit module reset, default digital 4
ControlVoltage · Arduino logic - SWCLKSWD pad
SWD clock for advanced/debug use
UnknownVoltage · 3V logic - SWDIOSWD pad
SWD data for advanced/debug use
UnknownVoltage · 3V logic - F.RSTfactory reset pad
Factory reset pad, tie to ground while powering up
Control
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