BLE application with nRF51822 – Introduction

In wireless communication protocols area, there are a lot of « standard » and let’s be honest, it’s pretty difficult to know what is the best fit for DIY project. The goal of this tutorial is to explain in painless way how developers can bring Bluetooth Low Energy technology in home projects thanks to nRF51822 Smart Beacon Kit.

nrf51 Nordic Semiconductor bluetooth smart beacon
nRF51822 Smart Beacon Kit

nRF51 is a BLE products family provided by Nordic Semiconductor.  It embed a ARM cortex M0 and a 2.4GHz radio frontend. Below the complete specifications of this chip:
  • 32-bit ARM Cortex M0 processor
  • 256kB flash / 16kB RAM
  • Full set of digital interfaces including: SPI/2-wire/UART
  • 10-bit ADC
  • 128-bit AES ECB/CCM/AAR co-processor
  • Quadrature demodulator
  • Low cost external crystal 16MHz 40ppm
  • Low power 16MHz crystal and RC oscillators
  • Ultra low-power 32kHz crystal and RC oscillators
  • Wide supply voltage range (1.8 V to 3.6 V)
  • On-chip DC/DC buck converter
  • Flexible and configurable 31 pin GPIO
  • Programmable Peripheral Interface PPI
  • Multi-protocol 2.4GHz radio
Nordic also provides BLE stack in order to develop quickly BLE applications. This means that developers don’t need to think about stack layers (HCI/L2CAP/GATT/GAP as you can see on the image below).
bluetooth and bluetooth low energy stack description
Indeed developing Bluetooth/BLE stack from scratch could be really difficult and a huge source of troubles. This evaluation board is an ideal product for every one who wants to develop on ARM based project. In the next post I will explain how to setup development environment on Mac OSX with GCC.