To test the failure using Thonny:
XIAO Hardware setup:
- Connect a 10K resister between 3v3 and D2.
- Connect a N/O switch between GND and D2.
- Connect your favorite serial monitor to D6 (and ground if necessary).
Install the ESP32_GENERIC_C6-20250911-v1.26.1.bin from MicroPython Downloads.
Copy the following program “main.py” to Thonny and save to ESP32C6 as main.py.
"""
Just report the reset_cause.
"""
from micropython import const
import os
import sys
import time
import machine
from machine import Pin, UART
LED_PIN = const(15)
def main():
reset_cause = machine.reset_cause()
# match reset_cause:
if reset_cause == machine.PWRON_RESET:
print('reset_cause = PWRON_RESET')
elif reset_cause == machine.HARD_RESET:
print('reset_cause = HARD_RESET')
elif reset_cause == machine.WDT_RESET:
print('reset_cause = WDT_RESET')
elif reset_cause == machine.DEEPSLEEP_RESET:
print('reset_cause = DEEPSLEEP_RESET')
elif reset_cause == machine.SOFT_RESET:
print('reset_cause = SOFT_RESET')
else:
print('reset_cause = Unknown_RESET')
if __name__ == '__main__':
# excpt_log = open('exception.txt', 'w')
start = time.ticks_ms()
try:
led = Pin(LED_PIN, Pin.OUT, value=0) # Turn LED(GPIO15) ON
uart = UART(1, baudrate=115200, tx=Pin(6), rx=Pin(7))
uart.init(115200, bits=8, parity=None, stop=1)
os.dupterm(uart, 0)
main()
print(f'Runtime was {time.ticks_diff(time.ticks_ms(), start)} millisecs.')
except Exception as e:
sys.print_exception(e) # , excpt_log)
# excpt_log.close()
led.value(1) # Turn LED OFF
Copy the following program “deepsleep.py” to Thonny and run it.
# now MicroPython v1.26.1 on 2025-09-11; ESP32C6 module with ESP32C6
# was MicroPython v1.24.0-preview.407.g197becbdc on 2024-10-09;
"""
Function Purpose
-------- -------
__main__ Setup
main Verify the door_sw is working, init and enter deepsleep
"""
# from circuitpython import const
import os
import sys
import time
import esp32
import machine
from time import sleep, ticks_ms, ticks_diff
from machine import Pin, UART, ADC
from esp32 import wake_on_ext1, WAKEUP_ALL_LOW
LED_PIN = const(15)
WAKE_UP_PIN = const(2)
def main():
global WAKE_UP_PIN
door_sw = Pin(WAKE_UP_PIN, Pin.IN) # pullup with 10K to 3v3
print("OK for 10 seconds, operate the switch & verify the value changes.")
for _ in range(20):
print(f'Mailbox door_sw is {"Closed" if door_sw.value() else "Open"}.')
sleep(0.5)
for sec in range(604800): # 7 days in seconds
if door_sw.value():
break
minutes, seconds = divmod(sec, 60)
hours, minutes = divmod(minutes, 60)
days, hours = divmod(hours, 24)
print(f'Waiting for door closure {days}:{hours:02}:{minutes:02}.{seconds:02}', end='\r')
sleep(1)
esp32.wake_on_ext1(pins=[door_sw], level=esp32.WAKEUP_ALL_LOW)
if door_sw.value(): # default (door_sw=closed=1) to DeepSleep
print('\n Going into DeepSleep for maximum of 30 seconds.')
sleep(1)
machine.deepsleep(29 * 1000)
print('\n Past deepsleep()')
if __name__ == '__main__':
print("Entry to deepsleep.py(__main__)")
led = Pin(LED_PIN, Pin.OUT, value=0) # light the LED
start = ticks_ms()
excpt_log = open('exception.txt', 'w')
try:
uart = UART(1, baudrate=115200, tx=Pin(6), rx=Pin(7))
uart.init(115200, bits=8, parity=None, stop=1)
os.dupterm(uart, 0)
main()
print(f'Runtime = {ticks_diff(ticks_ms(), start)} millisecs.')
except Exception as e:
sys.print_exception(e) # , excpt_log)
excpt_log.close()
led.value(1) # turn the LED OFF (program end)
Reference to “door closure” is the switch you wired between GND and D2.
When you see the “OK for 10 seconds” message operate the switch and the output should from “closed” to “open”. When you see the “Going into DeepSleep” before 30 seconds elapse press the switch and Thonny is disconnect but the serial monitor will report a reset_cause of DEEPSLEEP_RESET. Now when you run the deepsleep.py again the Mailbox door_sw will show “Open” although it should be Closed because the voltage on D2 is 3v3.
I believe the wake_on_ext1 is making changes to D2 operation that the DEEPSLEEP should be restoring (and isn’t). Whether I’m right or not there is something that is freezing D2 from reading 3v3 after DEEPSLEEP has awaken. Whether DEEPSLEEP is awaken from D2 or the 30 second timeout, D2 is still frozen as if the switch was pressed and it isn’t.
I find I have to press the BOOT button on the XIAO to restore D2 operation.
Anyone have a workaround?
Thanks, Morris
PJ 