Sample temperature from the CPU sensor, then halt after temperature exceeds threshold.

The Espressif documentation is decent, but finding critical information is often obfuscated. An article by CircuitLabs was most helpful.

Useful Reading

CircuitLabs (2025). ESP32 ULP Assembly Programming.
ESP32 ULP Assembly Programming

Espressif Documentation

• ULP Instruction Set
  https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/ulp_instruction_set.html

• ULP FSM (Finite State Machine) Guide
  https://docs.espressif.com/projects/esp-idf/en/release-v6.0/esp32/api-reference/system/ulp-fsm.html