Update and Recovery

Gecko OS is part of a larger sophisticated application framework installed on all Gecko OS devices. The framework provides a hardened bootloader, read/write file system, safemode recovery mechanism, and secure over-the-air (OTA) Device Firmware Update (DFU) capability.

Secure Update

Silabs manages a secure online Device Firmware Update (DFU) server that offers each Gecko OS device the ability to securely update individual files, applications or an entire firmware bundle. Use the dfu_update command to update device firmware.

The Device Firmware Update (DFU) process is secured by industry standard TLS/HTTPS using server and client certificates that forces:

HTTPS is the same security your web browser uses to make secure transactions with your bank over the internet. Silabs adds an additional layer of security, since the DFU server checks the unique security certificate and hardware UUID of each Gecko OS device that requests an update.

If a DFU fails to complete for some reason, you can resume it later. Rejoin the network and run the dfu_update command again.

The Gecko OS DFU feature uses the Device Management Server (DMS).

Note: To update from ZentriOS WL to Gecko OS, see Updating to Gecko OS.

The Device Management Server (DMS)

To update a Gecko OS device using Gecko OS, you need to sign up for an account with the Device Management Server (DMS) and then you need to claim your device.

You may also need to activate your device to a Gecko OS product.

The terms claim and activate are used in a special sense with the DMS, and are defined as follows.

To perform Gecko OS OTA update, the steps are:

Signing up with the DMS

To sign up for an account with the DMS, go to the Silabs DMS Sign up page:

https://dms.zentri.com/signup

During the sign up process, you will create a DMS username and password.

Claim Your Device

To claim your device, issue the dms_claim command:

dms_claim <dms_username> <dms_password>

After you have claimed the device, future DFU update requests are directed to the Device Management Service.

Update Gecko OS Using DFU

Once the device is claimed, update to the latest version of your Gecko OS product by issuing the dfu_update command..

Note: DFU requires a memory-intensive TLS connection, and may fail if memory is low. See Networking and Security, Increasing Available Memory for TLS.

If the dfu_update command fails with the message:

{"result":"fail","message":"device not claimed"}

then you need to claim the device before running the dfu_update command. See The Silabs DMS above.

The Gecko OS DMS Commands

When using Gecko OS, the dms_claim and dms_activatecommands are used to claim and activate devices:

Activate a Product by Product Code

To activate a device to a specific product, use the dms_activate command.

dms_activate <product code>

To update the device to the latest published firmware bundle for the product:

dfu_update

When issued with no arguments, the dfu_update command updates to the most recent firmware bundle version for the product, or does nothing if the device already has the most recent version installed.

Safe Mode

Safe mode operation is guaranteed in the unlikely event the device is configured in a way that causes repeated and/or unexpected reboots. The bootloader automatically switches to safe mode after eight exceptions occur with the offending boot application. Safe mode is indicated by the system.safemode.status variable.

It is easy to return the device to normal operation when the device is in safe mode. Follow the command sequence in the following table and your device will be back to normal in no time.

Gecko OS Commands Description 

get system.safemode.status
faults_print
faults_reset
faults_print
reboot


<- Check if the device is in safemode? 0 = no, 1 = yes
<- Print a list of faults (8 faults should print)
<- Reset faults counter
<- Check there are no more faults after reset
<- Reboot the device

In some cases, a misconfigured device may quickly return to safe mode since the device may be inadvertently setup to invoke a fault. If this occurs, we recommend the device is returned to factory reset.

Once in safe mode, the device boots into the kernel. The kernel provides the ability to update the firmware, or switch back to Gecko OS using the faults_reset command.

For a detailed discussion of recovery procedures, see the Recovery from Safemode application note.

Commands and Variables Available in Safe Mode

In safe mode a subset of the commands and variables is available.

Safe Mode Commands

Safe Mode Variables

Factory Reset

Factory reset returns the device to a known state.

The device may be factory reset by GPIO or by the Gecko OS factory_reset command.

After a successful factory reset, all variables are set to factory defaults and the device reboots.

See Configuration and Setup, Resetting Variable Values for details of reset types and the reset process.

Factory Reset GPIO

The factory reset GPIO is GPIO 0 on all Gecko OS devices. To perform a factory reset by GPIO:

Button 1 is wired to GPIO 0 on Silabs evaluation boards. On a Silabs evaluation board, to factory reset:

Note: GPIO 0 always acts as the factory reset GPIO. GPIO 0 may be configured to initialize to another GPIO function, but the factory reset function takes priority over other functions.

Factory Reset Command

Use the factory_reset command to perform a factory reset. To avoid accidental factory reset, the device Wi-Fi MAC address must be provided: