Release Notes

Version: Legato 19.04.0
Date: May 10, 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 19.04 Release:

Experimental Features Section

We are now releasing alpha and beta features as experimental features within Legato. The current experimental features are le_dcs Interface and Remote-procedure Call. Experimental features are not enabled by default in Legato and must be configured with Legato KConfig.

To enable Experimental Features within KConfig:

make menuconfig_<target>

General Setup
  -> Prompt for experimental (alpha-quality) features

Migrate from le_data to le_dcs

The le_data API (Data Connection le_data.api) has been refactored to use le_dcs (le_dcs Interface le_dcs.api). This addresses unexpected behaviors when using both le_data and le_dcs API simultaneously.

New wifi configuration APIs

Introduced new wifi APIs to configure access points for 802.11 n and/or ac (WiFi Access Point Service le_wifiAp.api).

Beta Features

Alpha Features

The following are the list of features that have been added into the 19.04 Release but are still being developed and should not be used on production targets. Please provide feedback for these features on our forums:

Legato RPC

Provide legato RPC as an experimental feature (Remote-procedure Call Remote procedure call). Please refer to getStartRPC Legato RPC on how to get started and also the current limitations.

Experimental IDE

The Legato team has launched the alpha version of a Legato Plugin for VSCode.

Fixed Issues

All changes are tagged in GitHub as "19.04.0". 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 19.04.0 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: