18.06.4 Release Notes

Release Date: Oct 23, 2018

See Licenses to view Legato AF Licensing Information.

The following provides a summary of changes that have been made in the 18.06 Legato AF Release.

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

18.06.4 Patch

The following issues have been fixed by the 18.06.4 patch:

  • A bug has been fixed that prevented the SPI service from working on wp85 targets. The fix changes the SPI driver to load on demand. The SPI driver is now loaded when the SPI service app starts and not at Legato start.

User Agreement Behavior Change: By default, user agreements are now disabled. This means that avcService automatically accepts requests from the server without asking for user approval. It initiates a connection to the server, downloads/installs packages and reboots the target if needed. Thus, if no control app for the AirVantage service is present on the target, the daemon is still able to update the target.

18.06.3 Patch

The following issues have been fixed by the 18.06.3 patch:

Modem Radio Control API: The following functions have been added to mrc API to support PCI scanning. The PCI scan is used to get the MCC/MNC for each neighboring cell ID:

18.06.2 Patch

The following issues have been fixed by the 18.06.2 patch:

A patch has been added to allow more time for the modem to start up. Legato will now uses the watchdog timer and fault action to recover any services that fail to start.

18.06.1 Patch

The following issues have been patched in 18.06.1:

A bug is fixed that caused a data corruption issue when performing a system update. If the update created a secure storage entry that was more then 4k in size the bug caused the last byte to be silently dropped.

New Features

The following are the list of new features that have been added into the 18.06 Release:

Modem Radio Control API

SAR (Specific Absorption Rate) is a measure of RF energy absorption by the human body. Users can dynamically select a pre-configured SAR backoff state in the modem so they can adjust the SAR depending on their needs.

The following functions have been added to the Modem Radio Control API:

eCall API

In test mode developers are able to retrieve and set the interval where the IVS remains registered in the network after the completion of the transmission of the test results to the System Operator. The default time value is set to 120 seconds.

The Psap Number functions now return values for LE_UNSUPPORTED and LE_OVERFLOW


A new function le_gnss_ConvertDataCoordinateSystem() can be called to convert a location data value from a coordinate system to another. Currently it is possible to convert the following data types:

  • Latitude
  • Longitude
  • Altitude

Beta Features

The following features have been added to the 18.06 Release and are feature complete but are still in a testing phase. Please provide feedback for these features on our forums.

Kernel Modules

Kernel Modules functionality has been added to support dependencies between kernel modules and dependencies between kernel modules and apps/components. We have also included functionality into the kernel module feature to bundle other files with the kernel module sources and provide scripts to load and unload the kernel module from your target.

Before building kernel modules into your Legato System you may have to perform some extra toolchain setup steps.

Alpha Features

The following are the list of features that have been added into the 18.06 Release but are still being developed and should not be used on production targets. Please provide feedback for these features on our forums:

Multiple SIM Support

The framework now contains support for multiple embedded SIM profiles and the ability to switch between the multiple SIMs and be managed by a subscription management server such as AirVantage.

Fixed Issues

All development work is tagged in GitHub as "18.06.0". 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 18.06.0 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