Lifecycle of an application

Important

This is the Azure Sphere (Legacy) documentation. Azure Sphere (Legacy) is retiring on 27 September 2027, and users must migrate to Azure Sphere (Integrated) by this time. Use the Version selector located above the TOC to view the Azure Sphere (Integrated) documentation.

All Azure Sphere applications, whether for the high-level or real-time capable cores, should be written to run continuously. If an application exits unexpectedly, system software automatically restarts it.

The Azure Sphere OS does not reset peripherals on start-up. Your high-level and real-time capable applications should ensure that peripherals are in a known-good state on start-up. For hardware-specific information about how to program peripherals for high-level and real-time capable applications, see the documentation from your hardware manufacturer. For information about the MT3620, see the published MT3620 Datasheet from MediaTek; if questions remain, you can request the MT3620 M4 Datasheet from Avnet by emailing Azure.Sphere@avnet.com.

High-level applications should exit only upon receiving a SIGTERM signal from the Azure Sphere OS. The Azure Sphere samples show how to handle this signal and terminate neatly. If an application fails to exit after it receives the SIGTERM signal, the Azure Sphere OS terminates with the SIGKILL signal. Applications should ensure that SIGKILL is never required.