That code was brill ... its a PITA to try to find exactly what you can and can't call though, you have to poke through the source looking for the IRAM tag. For what it's worth in case anyone cares. I'm finding that it takes around 1mSec from when I see the current begins to ramp up before my wake_st...

When level is high before entering deep sleep, set deep sleep to wake on level low.
When level is low, set deep sleep to wake on level high.


Would that work for you?

Still trying to get a handle on this .. hope people don't mind me adding findings here ROM functions can be found in https://github.com/espressif/esp-idf/tree/master/components/esp32/include/rom sleep related functions can be found in https://github.com/espressif/esp-idf/blob/master/components/esp32...

Apologies if this has already been asked. Is it possible to re-enter deep sleep from within esp_wake_deep_sleep()? Obviously I've tried, but if I call esp_sleep_enable_timer_wakeup(###) without even trying to call esp_deep_sleep_start() I get an rst:0x7 (TG0WDT_SYS_RESET),boot:0x13 (SPI_FAST_FLASH_B...

I have success with rom_phy_get_vdd33() , though it only seems to work when WiFi or BT is on. If WiFi is on the reading is occasionally wildly out. With just BT on it is pretty stable. Fortunately it doesn't take long at all to enable + disable BT in my setup() function before I enable WiFi. My boar...