Teseo III and Teseo GNSS Modules: Geofencing Subsystem

Introduction

Teseo III GNSS chips and modules feature a Geofence subsystem designed to notify the host when the current position falls inside or outside a set of pre-programmed circles. This subsystem supports up to 8 configurable circles, with 4 circles configurable directly in the firmware. It offers both polling and asynchronous notification methods and can be programmed using the NMEA command API.

Geofence in Polling Mode

This mode involves actively checking the geofence status.

Configure a Circle

Use the following NMEA command to configure a geofence circle:

Example configuration:

Check the Geofence Status

To query the current geofence status, use:

Replay Teseo III Status

The status of Teseo III can be replayed using:

Example status replay:

Circle Status Meaning

• 0: Status unknown (Circle disabled or No PVT solution available, e.g., during power-on)
• 1: PVT solution outside of the circle
• 2: PVT solution outside of the circle boundary
• 3: PVT solution inside of the circle

Geofence in Async Mode

This mode allows the module to asynchronously notify the host about geofence events.

Prepare the Geofence Async Mode

Configure the firmware to enable the asynchronous $PSTMGEOFENCE message in the message-list. This configuration is typically done once.

Geofence Runtime Async Mode

Configure a circle using the same command as in polling mode:

Example configuration:

When the PVT solution updates a circle status (e.g., entering or exiting a circle), Teseo III sends the following message:

Example async notification:

Note: Ensure the $PSTMGEOFENCE message is sent only once per circle status update.

Documents & Related Resources

Additional information and resources are available on st.Com.

Teseo III

• Webpage: ST Teseo III
• Datasheets

Teseo Modules

• Webpage: ST Teseo Modules
• Datasheets

Teseo-Suite

• Webpage: ST Teseo-Suite
• Datasheet
• Install program
• User manual and Training material

GNSS ICs Overview

ST's Teseo family of Global Navigation Satellite System (GNSS) ICs offers high positioning accuracy and indoor sensitivity combined with powerful processing capabilities. They simultaneously support multiple global navigation systems including BeiDou, Galileo, GLONASS, GPS, and QZSS. Teseo III, the latest generation, provides reduced power consumption, carrier-phase tracking for higher accuracy, and support for Read-only Memory (ROM). The product offering includes standalone positioning chips (SAL) and configurable system-on-chips (SoCs). SAL devices come with embedded GNSS firmware for all positioning operations. SoCs offer processing power and memory for customers to integrate their own code or specific IPs with ST's GNSS library. Both solutions are compatible with the TESEO-DRAW sensor fusion firmware for dead-reckoning and assisted navigation. Teseo devices are suitable for e-call and telematics systems, personal navigation devices (PNDs), handheld devices, and marine and in-car navigation systems.