ESP32 + AC-Dimmer: Guru Meditation Error und IRAM_ATTR — Ursachen und Lösung 26.02.2026 0 424 TL;DR: If your ESP32 with an AC dimmer crashes ("Guru Meditation Error" or "Cache disabled but cached memory region accessed"), the cause is that the zero-cross ISR handler is not marked with IRAM_ATT... ac-dimmer ESP32 IRAM_ATTR troubleshooting WiFi Mehr lesen