🛠 Deep-sleep 7 µA : le bouton qui doit être dans le domaine LP

The ESP32-H2 is designed for battery-powered mesh networks: typical deep-sleep current is 7 µA with 4 KB of LP SRAM retained, light-sleep is 25–85 µA, and power-off is 1 µA (datasheet, at 3.3 V and 25 °C). Tutorial: a button wakes up the H2, you perform a radio burst, then return to deep-sleep. CRITICAL rule: GPIO0–5 and GPIO22–27 are inactive during deep-sleep — only the LP domain can wake up the chip. Therefore, connect a button to GPIO6, configure esp_sleep_enable_ext0_wakeup for a LOW level, then call esp_deep_sleep_start. Also watch out for GPIO12: it is multiplexed with the VBAT/VDDA_PMU power pins — in a battery-powered design, finalize your power supply scheme before reusing it as an IO, and never leave CHIP_EN floating to avoid random behavior. Hardware detail: the first DevKitM-1 boards (before February 2024) ship without the 32.768 kHz LP crystal — the RTC will be inaccurate and average power consumption higher until you solder it. The DevKitM-1’s J5 current measurement jumper lets you verify the advertised 7 µA with a multimeter.