52 December 2016
THE DESIGN CYCLE n BY FRED EADY
Flight-Tested Hardware
Since we’ve already designed and assembled some
known working BLE hardware, why not use it as the
target for the new GPIO firmware we’re going to create.
Our compiled ARM Cortex-M code will be loaded into
the Raytac BLE module mounted on the nRF52832
development board shown in Photo 1. I’ve chosen to
use the Raytac module because it is a true Nordic
Semiconductor nRF52832 reference design housed
in module form. Plus, Raytac was the only third-party
module provider that readily offered the nRF52832
in module form.
The nRF52832 development board design
includes a 32.768 kHz crystal and a pair of LEDs.
The nRF52832 programming portal is composed
of a single 1.27 mm 10-pin male header. The
development board brings all available nRF52832
GPIO out to standard 0.1 inch pitch header
positions. The vertical header position on the far left
of the nRF52832 board can be used to mount it on
a solderless breadboard.
Once mounted on a solderless breadboard,
power for the nRF52832 can be obtained via the
VDD and GND pins. The nRF52832 GPIO pins
can be assigned to any of the peripherals. So, this
vertical column of GPIO pins can be used to form
a UART, SPI portal, I2C portal, PWM portal, ADC
portal, or just plain GPIO. Schematic 1 offers a full
graphical depiction of the nRF52832 development board
design.
Firmware Development Platform
The Keil MDK for Cortex-M along with version 12 of
the nRF5 SDK will be used to compose and compile our
e have proven that the Nordic Semiconductor nRF52832 is
relatively easy to activate in the role of a BLE (Bluetooth Low
Energy) peripheral device. However, the most intriguing thing
about the Nordic nRF52832 is its very powerful 32-bit ARM
Cortex-M4F CPU, which is chunking bits at 64 MHz. This time around,
instead of thinking radio, we’ll focus on treating the nRF52832 as a very
powerful microcontroller. Let’s have some fun.
W
Exploring the Nuances of Nordic
Semiconductor’s nRF52832’s
Timer and GPIO Peripherals
n PHOTO 1. The Raytac module contains a regulation Nordic
nRF52832 supported by the appropriate capacitors, crystals, and
inductors. An external 32.768 kHz crystal completes the hardware
design.
