/*
Deep Sleep with Touch Wake Up
=====================================
This code displays how to use deep sleep with
a touch as a wake up source and how to store data in
RTC memory to use it over reboots
ESP32 can have multiple touch pads enabled as wakeup source
ESP32-S2 and ESP32-S3 supports only 1 touch pad as wakeup source enabled
This code is under Public Domain License.
Author:
Pranav Cherukupalli <[email protected]>
*/
#if CONFIG_IDF_TARGET_ESP32
#define THRESHOLD 40 /* Greater the value, more the sensitivity */
#else //ESP32-S2 and ESP32-S3 + default for other chips (to be adjusted) */
#define THRESHOLD 5000 /* Lower the value, more the sensitivity */
#endif
RTC_DATA_ATTR int bootCount = 0;
touch_pad_t touchPin;
/*
Method to print the reason by which ESP32
has been awaken from sleep
*/
void print_wakeup_reason(){
esp_sleep_wakeup_cause_t wakeup_reason;
wakeup_reason = esp_sleep_get_wakeup_cause();
switch(wakeup_reason)
{
case ESP_SLEEP_WAKEUP_EXT0 : Serial.println("Wakeup caused by external signal using RTC_IO"); break;
case ESP_SLEEP_WAKEUP_EXT1 : Serial.println("Wakeup caused by external signal using RTC_CNTL"); break;
case ESP_SLEEP_WAKEUP_TIMER : Serial.println("Wakeup caused by timer"); break;
case ESP_SLEEP_WAKEUP_TOUCHPAD : Serial.println("Wakeup caused by touchpad"); break;
case ESP_SLEEP_WAKEUP_ULP : Serial.println("Wakeup caused by ULP program"); break;
default : Serial.printf("Wakeup was not caused by deep sleep: %d\n",wakeup_reason); break;
}
}
/*
Method to print the touchpad by which ESP32
has been awaken from sleep
*/
void print_wakeup_touchpad(){
touchPin = esp_sleep_get_touchpad_wakeup_status();
#if CONFIG_IDF_TARGET_ESP32
switch(touchPin)
{
case 0 : Serial.println("Touch detected on GPIO 4"); break;
case 1 : Serial.println("Touch detected on GPIO 0"); break;
case 2 : Serial.println("Touch detected on GPIO 2"); break;
case 3 : Serial.println("Touch detected on GPIO 15"); break;
case 4 : Serial.println("Touch detected on GPIO 13"); break;
case 5 : Serial.println("Touch detected on GPIO 12"); break;
case 6 : Serial.println("Touch detected on GPIO 14"); break;
case 7 : Serial.println("Touch detected on GPIO 27"); break;
case 8 : Serial.println("Touch detected on GPIO 33"); break;
case 9 : Serial.println("Touch detected on GPIO 32"); break;
default : Serial.println("Wakeup not by touchpad"); break;
}
#else
if(touchPin < TOUCH_PAD_MAX)
{
Serial.printf("Touch detected on GPIO %d\n", touchPin);
}
else
{
Serial.println("Wakeup not by touchpad");
}
#endif
}
void setup(){
Serial.begin(115200);
delay(1000); //Take some time to open up the Serial Monitor
//Increment boot number and print it every reboot
++bootCount;
Serial.println("Boot number: " + String(bootCount));
//Print the wakeup reason for ESP32 and touchpad too
print_wakeup_reason();
print_wakeup_touchpad();
#if CONFIG_IDF_TARGET_ESP32
//Setup sleep wakeup on Touch Pad 3 + 7 (GPIO15 + GPIO 27)
touchSleepWakeUpEnable(T3,THRESHOLD);
touchSleepWakeUpEnable(T7,THRESHOLD);
#else //ESP32-S2 + ESP32-S3
//Setup sleep wakeup on Touch Pad 3 (GPIO3)
touchSleepWakeUpEnable(T3,THRESHOLD);
#endif
//Go to sleep now
Serial.println("Going to sleep now");
esp_deep_sleep_start();
Serial.println("This will never be printed");
}
void loop(){
//This will never be reached
}