I am trying to understand the difference between RTC_NOINIT_ATTR vs RTC_DATA_ATTR (slow vs fast memory) but cannot see a clear definition and examples when to use which - not even on the original espressif websites: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-guides/memory-types.html
Can anyone clarify it using concrete examples?
In my case, I need to store a struct into RTC memory before going to deep sleep and the same struct values should be available after waking up (regardless whether it was based on the timers or external events or WDT). Which one shall I use RTC_NOINIT_ATTR or RTC_DATA_ATTR and why?