nRF52 Adafruit Feather
Overview
The nRF52 Adafruit Bluefruit Feather hardware provides support for the Nordic Semiconductor nRF52832 ARM Cortex-M4F CPU and the following devices:
NVIC
RTC
UART
GPIO
FLASH
RADIO (Bluetooth Low Energy)
Segger RTT (RTT Console)
More information about the board and its features can be found at the Adafruit Feather nRF52 Bluefruit Learning Guide [1]. The Nordic Semiconductor Infocenter [4] contains the processor’s information and the datasheet.
Hardware
nRF52832 ARM Cortex-M4F processor at 64 MHz
32.768 kHz crystal oscillator
512 KiB flash memory and 64 KiB of SRAM
Battery connector and charger for 3.7 V lithium polymer batteries
Charging indicator LED
2 User LEDs
Reset button
SWD connector
USB serial converter
Supported Features
The nrf52_adafruit_feather board supports the hardware features listed below.
- on-chip / on-board
- Feature integrated in the SoC / present on the board.
- 2 / 2
-
Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files. -
vnd,foo -
Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.
Type |
Location |
Description |
Compatible |
|---|---|---|---|
CPU |
on-chip |
ARM Cortex-M4F CPU1 |
|
ADC |
on-chip |
Nordic Semiconductor nRF family SAADC node1 |
|
ARM architecture |
on-chip |
Nordic UICR (User Information Configuration Registers)1 |
|
on-chip |
Nordic nRF family BPROT (Block Protection)1 |
||
on-chip |
Nordic EGU (Event Generator Unit)6 |
||
on-chip |
Nordic nRF family MWU (Memory Watch Unit)1 |
||
Audio |
on-chip |
Nordic PDM (Pulse Density Modulation interface)1 |
|
Clock control |
on-chip |
Nordic nRF clock control node1 |
|
Comparator |
on-chip |
Nordic nRF COMP (analog COMParator)1 |
|
Counter |
on-chip |
Nordic nRF timer node5 |
|
Cryptographic accelerator |
on-chip |
Nordic ECB (AES electronic codebook mode encryption)1 |
|
on-chip |
Nordic nRF family CCM (AES CCM mode encryption)1 |
||
Debug |
on-chip |
ARMv7 instrumentation trace macrocell1 |
|
Flash controller |
on-chip |
Nordic NVMC (Non-Volatile Memory Controller)1 |
|
GPIO & Headers |
on-chip |
NRF5 GPIOTE1 |
|
on-chip |
NRF5 GPIO1 |
||
on-board |
GPIO pins exposed on Adafruit Feather headers1 |
||
I2C |
on-chip |
Nordic nRF family TWI (TWI master)1 |
|
on-chip |
Nordic nRF family TWIM (TWI master with EasyDMA)1 |
||
I2S |
on-chip |
Nordic I2S (Inter-IC sound interface)1 |
|
Input |
on-board |
Group of GPIO-bound input keys1 |
|
Interrupt controller |
on-chip |
ARMv7-M NVIC (Nested Vectored Interrupt Controller)1 |
|
LED |
on-board |
Group of GPIO-controlled LEDs1 |
|
on-board |
Group of PWM-controlled LEDs1 |
||
Miscellaneous |
on-chip |
Nordic FICR (Factory Information Configuration Registers)1 |
|
on-chip |
Nordic nRF family PPI (Programmable Peripheral Interconnect)1 |
||
MTD |
on-chip |
Flash node1 |
|
on-board |
Fixed partitions of a flash (or other non-volatile storage) memory1 |
||
Networking |
on-chip |
Nordic nRF family RADIO peripheral1 |
|
on-chip |
Nordic nRF family NFCT (Near Field Communication Tag)1 |
||
Pin control |
on-chip |
The nRF pin controller is a singleton node responsible for controlling pin function selection and pin properties1 |
|
Power management |
on-chip |
Nordic nRF power control node1 |
|
PWM |
on-chip |
||
on-chip |
nRFx S/W PWM1 |
||
Regulator |
on-chip |
Nordic nRF5X regulator (fixed stage of the core supply)1 |
|
Retained memory |
on-chip |
Nordic GPREGRET (General Purpose Register Retention) device2 |
|
RNG |
on-chip |
Nordic nRF family RNG (Random Number Generator)1 |
|
RTC |
on-chip |
Nordic nRF RTC (Real-Time Counter)3 |
|
Sensors |
on-chip |
Nordic nRF family TEMP node1 |
|
on-chip |
Nordic nRF quadrature decoder (QDEC) node1 |
||
Serial controller |
on-chip |
Nordic nRF family UART1 |
|
SPI |
on-chip |
Nordic nRF family SPI (SPI master)3 |
|
SRAM |
on-chip |
Generic on-chip SRAM description1 |
|
Timer |
on-chip |
ARMv7-M System Tick1 |
|
Watchdog |
on-chip |
Nordic nRF family WDT (Watchdog Timer)1 |
Connections and IOs
The Adafruit Feather nRF52 Bluefruit Learning Guide [1] has detailed information about the board including pinouts [3] and the schematic [2].
LED
LED0 (red) = P0.17
LED1 (blue) = P0.19
Programming and Debugging
The nrf52_adafruit_feather board is available in two different versions:
- Adafruit Feather nRF52 Pro with myNewt Bootloader [6]
This board version is the recommended one to use. It has the SWD header already populated and comes with the Mynewt serial bootloader installed by default.
- Adafruit Feather nRF52 Bluefruit LE [5]
This board is identical to the board above, but the SWD header is not populated and ships with an Arduino friendly bootloader. To be able to work with this version a 2*5pin 0.5” SWD header (e.g. Adafruit SWD connector [7]) needs to be soldered.
Applications for the nrf52_adafruit_feather board configuration can be
built, flashed, and debugged in the usual way. See Building an Application
and Run an Application for more details on building and running.
Flashing
Flashing Zephyr onto the nrf52_adafruit_feather board requires an external
J-Link programmer. The programmer is attached to the X1 SWD header.
Follow the instructions in the Nordic nRF5x Segger J-Link page to install and configure all the necessary software. Further information can be found in Flashing. Then build and flash applications as usual (see Building an Application and Run an Application for more details).
Here is an example for the Hello World application.
Build the Zephyr kernel and the Hello World sample application:
west build -b nrf52_adafruit_feather samples/hello_world
Connect the Adafruit nRF52 Feather to your host computer using USB
Run your favorite terminal program to listen for output.
$ minicom -D <tty_device> -b 115200
Replace
<tty_device>with the port where the nRF52 Adafruit Feather board can be found. For example, under Linux,/dev/ttyUSB0.Flash the image:
west build -b nrf52_adafruit_feather samples/hello_world west flash
You should see “Hello World! nrf52_adafruit_feather” in your terminal.
Debugging
The nrf52_adafruit_feather board does not have an on-board J-Link debug IC
as some nRF5x development boards, however, instructions from the
Nordic nRF5x Segger J-Link page also apply to this board, with the additional step
of connecting an external debugger.