Inkplate 6COLOR – Deep Sleep

Deep sleep is how you get a sketch to run for months on a battery. E-paper needs no power to hold its image, so between refreshes the board can sit at about 18 µA.

Simple deep sleep

ℹ️

When your ESP32 wakes up from deep sleep, it performs a reset and runs main.py again. That means your main script runs again on every wake-up.

⚠️

Make sure you've uploaded a main.py file to the ESP32. Put the code you want to run after each wake-up inside it.

Basic example of keeping a counter in RTC memory using raw bytes while ESP32 is in deep sleep.

from inkplate6_color import Inkplate
import machine
import time

# Create a RTC object that stores states between deep sleep cycles
rtc = machine.RTC()

# Read stored bytes from memory
raw = rtc.memory()

# If we have at least 1 stored byte, set as counter,
# otherwise start from 0
count = raw[0] if raw and len(raw) >= 1 else 0

inkplate = Inkplate()

inkplate.begin()

inkplate.clear_display()

# Check for reset reason and print message accordingly
if machine.reset_cause() == machine.DEEPSLEEP_RESET:
    inkplate.println("Woke up from sleep")
    # Increment counter
    count = count + 1
else:
    count = 1
    inkplate.println("Cold boot / soft reset")

# Write one byte back to RTC memory
rtc.memory(bytes([count]))

inkplate.print(f"Count: {count}")
inkplate.display()

# Important delay before going to sleep when writing scripts
# Wait 10 seconds so you can 'catch' it awake to upload new code later on
time.sleep(10)

# Deep sleep for 10 seconds (10000 milliseconds)
machine.deepsleep(10000)

machine.reset_cause()

Get the reset cause.

Returns type: machine.CONSTANT

ℹ️

See constants for possible return values.

machine.deepsleep()

Puts the ESP32 into deep sleep for the given number of milliseconds. Call it with no argument to sleep until a wake source fires.

Function parameters:

Type	Name	Description
`int`	`sleep_time_ms`	Deep sleep duration in milliseconds

Wake on button press

import esp32
import machine
import time

# Define a wake up pin on GPIO 36 (wake button)
wake1 = machine.Pin(36, mode = machine.Pin.IN)

# Set ext0 as a wake up source when pin goes LOW
esp32.wake_on_ext0(pin = wake1, level = esp32.WAKEUP_ALL_LOW)

print('Im awake. Going to sleep in 10 seconds')
time.sleep(10)

print('Going to sleep now')
machine.deepsleep()

esp32.wake_on_ext0()

This function uses the external wakeup feature of the RTC_IO peripheral.

Returns type: none

Function parameters:

Type	Name	Description
`machine.Pin`	`Pin`	GPIO number used as wakeup source. Only GPIOs with RTC functionality can be used.
`int`	`level`	The input level that triggers wake-up

Full example

deep_sleep.py

Count deep sleep cycles using RTC memory and show the count on the screen.

Simple deep sleep​