Developing Bluetooth Low Energy products with nRF5 SDK and SoftDevices

Still a valid option

Full Bluetooth features now with scope for future demands

For the nRF52 Series developing Bluetooth LE products with the nRF5 SDK and SoftDevices is still a valid option, especially if you are familiar with it and don't require an RTOS or features added after Bluetooth 5.0. If not, please consider using the nRF Connect SDK.

The nRF5 SDK is very mature and is used on millions of Bluetooth LE products to date. It is qualified to Bluetooth 5.1 and supports all of the Bluetooth LE features up to and including Bluetooth 5. Read below for more information. It supports all nRF51 and nRF52 Series SoCs.

We understand that a rich selection of well-tested, reliable software forms an integral part of designing your wireless product. Our unrivalled selection of SDK examples, robust and predictable communication stacks and development software will help you achieve success in line with your project’s goals.

All software we distribute for your application is developed by Nordic and tested in-house. Any open-source code that we re-distribute comes from projects we contribute to and ensures the quality of the solution on Nordic devices. This means we always have control of the features we offer and the testing procedures that deliver quality.

We offer two types of software for developing your Bluetooth LE product:

• Protocol stacks: We call them SoftDevices
• Software development kits: nRF5 SDK

The software development kits for nRF52 and nRF51 Series and the range of SoftDevices are designed to work together seamlessly, offering you as a developer an easy-to-use solution for building wireless applications.


Software architecture

Engineered for performance, energy efficiency and ease of use

The Nordic software architecture is unique. It is designed to make developing Bluetooth applications as simple and intuitive as possible, whilst also maintaining consistent and reliable performance at all levels.

There is a fundamental split in how the software architecture is made up, this is between the protocol stack and associated radio management functions, and the application itself.

This means less complicated application code and more reliable operation as you run through develop and compile iterations.

Your application which will usually incorporate elements of our nRF5 SDK interfaces to the protocol stack, known as a SoftDevice, via an API.

The SoftDevice is is event-driven and has no runtime dependencies.



The nRF5 SDK

Click to read more and download


The Bluetooth LE and ANT software development kit

The nRF5 SDK is a high quality, thoroughly tested software development kit to accelerate your software development efforts for the nRF52 and nRF51 Series SoCs. It contains hundreds of useful firmware modules and examples to assist in building your application.

SoftDevice feature comparison

SoftDevice S112 S113  S122  S132 S140
Compatible SoCs nRF52805, nRF52810, nRF52811, nRF52820, nRF52832 nRF52805, nRF52810, nRF52811, nRF52820, nRF52832, nRF52833, nRF52840 nRF52811, nRF52820, nRF52833 nRF52810, nRF52832 nRF52811, nRF52820, nRF52833, nRF52840
Bluetooth 5.1 qualified Yes Yes Yes Yes Yes
High-throughput 2 Mbps  Yes Yes Yes Yes
Long Range

Advertising Extensions 

  Yes Yes
CSA #2 Yes Yes Yes Yes Yes
Roles Peripheral + Broadcaster Peripheral + Broadcaster  Central + Observer All roles All roles
Links 4 concurrent 4 concurrent 8 concurrent 20 concurrent 20 concurrent
Configurable roles/bandwidth Yes Yes Yes Yes Yes
LE Secure connections Yes  Yes Yes Yes Yes 
Privacy 1.2 Yes  Yes Yes Yes Yes
LE Packet Length Extensions 
Yes Yes
Configurable ATT MTU  Yes  Yes Yes Yes
Custom UUID Yes  Yes Yes Yes
L2CAP CoC No  Yes
Yes Yes
Configurable ATT table Yes  Yes Yes Yes Yes


Feature-rich Bluetooth LE protocol stack

For the nRF52 Series

SoftDevice S140

SoftDevice S140 is a feature-rich Central and Peripheral Bluetooth LE protocol stack for the nRF52811, nRF52820, nRF52833 and nRF52840 SoCs.

Bluetooth 5.1 qualified
High-throughput 2 Mbps
Long Range
Advertising Extensions
CSA #2
LE Secure Connections
Privacy 1.2
Configurable ATT Table
Configurable ATT MTU
Custom UUID
LE Data Packet Length Extension
L2CAP connection-oriented channels
Concurrent multiprotocol support

ANT + Bluetooth LE protocol stacks

For the nRF52 Series

ANT + Bluetooth LE protocol stack

For the nRF51 Series

S310: Bluetooth 4.1 and ANT

The S310 is a combined Peripheral Bluetooth LE and ANT protocol stack for the nRF51422 that supports concurrent operation and all ANT features.
It is distributed and Bluetooth qualified by Garmin Canada, Inc.

15 individual configurable channels
Broadcast, acknowledged, burst transfer
Device search, pairing and proximity
Advanced burst transfer mode

Concurrent link as a Peripheral and Broadcaster

Configurable ATT Table

Privacy 1.1

Security mode 1 - Levels 1, 2 and 3

Custom UUID support

Support for concurrent multi-protocol with 2.4 GHz proprietary protocols

nRF51 Series

SoftDevice feature comparison

 SoftDevice S110  S120 S130
Supported SoC  nRF51422, nRF51822 nRF51422, nRF51822 nRF51422, nRF51822
Bluetooth 5  No No No
2 Mbps   No No No
Long range  No No No
Advertising Extensions   No No No
CSA #2  No No No
 Roles  Peripheral + Broadcaster All roles All roles
Links  1 8 concurrent as central or 1 as peripheral 8 concurrent as central and 1 as peripheral
Configurable roles/bandwidth  No No Yes
LE Secure connections  No No Yes
LL Privacy   No No No
LE Packet Length Extensions   No No No
Configurable ATT MTU   No No No
Custom UUID  Yes Yes
L2CAP CoC  No No No
Configurable ATT table  No No No



Latest news

diagram, schematic
25 May 2023

Nordic ranked number 26 on prestigious list of 500 companies...

Read More
25 May 2023

Fanstel’s WT02E40E Series modules employ Nordic’s nRF5340 So...

Read More
22 May 2023

The OctoNet ON-x00-15 Bluetooth positioning gateway employs ...

Read More