Release Notes

Version: Legato 19.02.0
Date: March 22nd, 2019
Legato Application Framework Licensing Information

Visit the release page to download the tarball, clone the repositories from GitHub, or view previous released versions.

Get started with the latest version of Legato by installing the SDK through Leaf.

Search for the latest version for your target (using wp76xx as an example):

$ leaf search -t wp76xx -t latest

Update your profile to the latest version:

$ leaf update

New Features

List of new features in the 19.02 Release:


The Legato Application Framework now includes a KConfig menu system for configuring the Framework including:

  • General build parameters
  • Framework flags and options
  • Module specific flags and options
  • New Experimental Features

Legato KConfig KConfig provides a unified mechanism for configuring the framework and service builds. This includes target selection, enabling security and diagnostic features, and many others. The full list of options may be found at KConfig Options. KConfig replaces a mixture of environment variables and preprocessor defines which were previously used to set the parameters of the build.

Legato uses kconfig-frontends to manage KConfig files and configuration. This is a version of the Linux kernel's KConfig system that has been extracted and tweaked for independent use.

Binary Support within ConfigTree

The config tree API (c_le_cfg le_cfg.api) now includes support for Binary objects within the Config Tree. New functions have been added to get, set and quick set of binary objects.

devMode Enhancements

The following Linux utilities have been added to the devMode app and are only available after you install devMode on your target device:

  • tcpdump - a traffic monitoring tool
  • iperf3/ - a network speed test tool
  • lsusb/usb-devices - lists all usb devices on a target
  • lsof - lists open files on a target


The AirVantage Platform Service now supports secured SMS wake-up requests from the AirVantage Service.

Beta Features

The following features have been added to the 19.02 Release and are feature complete but are still in a testing phase. Please provide feedback for these features on our forums.

Alpha Features

The following are the list of features that have been added into the 19.02 Release but are still being developed and should not be used on production targets. Please provide feedback for these features on our forums:

AirVantage CoAP

The AirVantage constrained application protocol is under development. le_coap.api is included in the interfaces directory but is only in a prototype state and should not be used on production targets at this time.

New Data Connection Service

A new Data Connection Service is under development. le_dcs.api is included in the interfaces directory but is only in a prototype state and should not be used on production targets at this time.

Fixed Issues

All changes are tagged in GitHub as "19.02.0". The full list of changes and commit messages can be found on GitHub.

This is only the list of fixes for the Application Framework and Platform Services, for the list of changes in the Platform Adapters and AVC Service view the commits under the tag 19.02.0 in individual repositories on GitHub.

Known Issues

Constraints and Limitations

Dev Machine Linux Version

To develop applications within the Legato Application Framework, a current supported Long Term Support version of Ubuntu Linux is required on your dev machine (or running in a virtual box on Windows). Ubuntu 18.04 is the current recommended version to use on your dev machine.

ECM-USB modem manager issue

Ubuntu 15.10 and newer has Modem Manager version 1.4.12-1ubuntu1 installed by default which conflicts with the ECM-USB driver when connecting a target. Modem manager may cause the Ubuntu Network Manager to crash on your host and/or your target device to become unavailable over USB.


  • NetworkManager crashing when plugging into your device over USB, or
  • The target device becomes inaccessible after 30 seconds.

Recommended Work Around: