18.09.2 Release Notes

Release Date: May 3rd, 2019

See Licenses to view Legato AF Licensing Information.

The following provides a summary of changes that have been made in the 18.09 Legato AF Release.

Download the source code and get started with building Legato AF.

18.09.2 Patch

The ability to use secure SMS to trigger a connection from a target to AirVantage has been disabled.

18.09.1 Patch

The 18.09.1 patch introduces a fix to improve the fwupdate process during poor network conditions. The curl low speed limit timeout and retry timers have been tweaked to allow more time for fwupdate to complete before retrying.

New Features

The following are the list of new features that have been added into the 18.09 Release:

STRUCT user type

STRUCT , a new user defined type can now be used in definition files. A structure is used to define a collection of data, similar to a C struct. A STRUCT can contain members of any type, including strings, arrays, and other STRUCTs.

SMACK onlycap

SMACK onlycap enablement is a new feature in Legato, by default the feature is turned off.

To enable SMACK onlycap the framework must be made with the disable SMACK onlycap flag set to 0:


App/Component Directory and File Access

New Features have been allowing developers to specify directory and file access to applications.

  • Add directories to an application visit the requires: dir: section in the .adef
  • Add files to an application visit the requires: file: section in the .adef
  • Add directories to a component visit the requires: dir: section in the .cdef
  • Add files to a component visit the requires: file: section in the .cdef

GNSS Leap Seconds

The GNSS API now includes a function to get the Leap Seconds event. The function returns current GPS time, current leap seconds, next leap second event time, and next leap seconds.

Beta Features

The following features have been added to the 18.09 Release and are feature complete but are still in a testing phase. Please provide feedback for these features on our forums.

Automatic SIM Selection

The Automatic Sim selection feature is relevant for modules that use an internal SIM card. When enabled, the module automatically selects a SIM slot according to the following rule:

  • If an external SIM is inserted in slot 1 then select it. Otherwise, fallback to the internal SIM card.

Alpha Features

The following are the list of features that have been added into the 18.09 Release but are still being developed and should not be used on production targets. Please provide feedback for these features on our forums:

Modem Radio Control API

The network scan can now obtain the Network global Celular identifier when performing a network scan by using the function le_mrc_GetCellularNetworkGlobalCellId().

Multiple SIM Support

The framework now provides support for multiple embedded SIM profiles and administration by a subscription management server such as AirVantage.

Fixed Issues

All development work is tagged in GitHub as "18.09.0". The 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 18.09.0 in the 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 16.04 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:

Sierra Wireless Toolchain Install

There is currently an error with setting up the WP76XX and WP77XX toolchain and the toolchain only partially installs. The part of the script to install and setup the kernel headers does not run and produces the following errors:

scripts/kconfig/Makefile:36: recipe for target 'silentoldconfig' failed
make[2]: *** [silentoldconfig] Error 1
Makefile:546: recipe for target 'silentoldconfig' failed
make[1]: *** [silentoldconfig] Error 2
make: *** No rule to make target 'include/config/auto.conf', needed by 'scripts'.  Stop.

To resolve this remove the installed toolchain and reinstall with sudo privileges.

Example of setting up the toolchain for a 64bit dev machine and a WP76 module with product release 9:

$ rm -rf /opt/swi/y22-ext
$ sudo poky-swi-ext-glibc-x86_64-meta-toolchain-swi-ext-armv7a-neon-toolchain-swi-ext-2.2.3.sh