[Bug]: Power Resuming after deep sleep

[mentanah]

Category

Hardware Compatibility

Hardware

T-Beam v1.2 with AXP2101

Firmware Version

2.5.18.89ebafc

Description

System: t-beam with latest firmware
Powering with battery and charging with solar panel over USB

For meshtastic a good node coverage is crucial and there fore exposed placed solar powered nodes are often physical hard accessible. Once the AXP2101 chip detects a low battery the MCU puts the device into deep sleep!
here is the place in the code:

firmware/src/PowerFSM.cpp

Line 65 in cdcbf4c

static void lowBattSDSEnter()

Unfortunately only pressing a button let the node resume to life. Pushing RST resets the device and pushing the GPIO38 button wakes from deep sleep and lets the device resume to power.

Repowering over USB DOES NOT exit the deep sleep state, since interrups from the AXP are ignored in firmware:

firmware/src/Power.cpp

Line 776 in cdcbf4c

// WE no longer use the IRQ line to wake the CPU (due to false wakes from sleep), but we do poll

So once the device is in deep sleep you have to drive to the node and push a button, this imho contradicts the spirit of meshtastic and self-sufficient systems.

Suggestion:
Shutting the device always down on client mode! Then a repowering of the USB brings the device back to life...

Relevant log output

No response

[fifieldt]

Thanks for the report.

After reading, I'm not sure what we can do in firmware to assist this. It might be simpler to solve in hardware....

[mentanah]

Why Not schutting off the device in lowBattSDSEnter() as in shutdownEnter()?