ESP32 touch detection - mqtt - deepsleep example

esp32-touch-deepsleep-mqtt.ino

/*
Example code: Detects a touch input which wakes up the esp32 from deepsleep. 
Then connects to a WiFi and post the touch event via MQTT. 
After finishing this the esp32 will go back to deppsleep.

This whole process takes around 800ms to finish.


author: @robertschnuell
https://interaktives.design



*/




#include "Arduino.h"
////// NETWORK ////////
#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>

////// NETWORK ////////
IPAddress server(192, 168, 0, 2);
const char* ssid = "............";
const char* password = "..........";
WiFiClient ethClient;
PubSubClient client(ethClient);
char message_buff[100];


IPAddress local_IP(192, 168, 0, 105);
IPAddress gateway(192, 168, 0, 254);
IPAddress subnet(255, 255, 255, 0);




#define Threshold 40

touch_pad_t touchPin;




void wakeupCheckProcess() {


  esp_sleep_wakeup_cause_t wakeup_reason;

  wakeup_reason = esp_sleep_get_wakeup_cause();


  if(wakeup_reason == 4) {
    touch_pad_t pin;

    touchPin = esp_sleep_get_touchpad_wakeup_status();

    if(touchPin == 3) {
      connect();
      checkConnection();
      client.publish("topic/touch","touched");
      delay(500);

    }

  }

}


void setup(){


Serial.begin(115200);


  wakeupCheckProcess();






// deepsleep functions
  touchAttachInterrupt(T3, callback, Threshold);   //Interuppt to wake up via touch
  esp_sleep_enable_touchpad_wakeup(); // define wakeup via touch
  esp_deep_sleep_start(); // go to sleep
}




// Placeholders
void loop(){
  //Limbus
}
void callback(){
  // nice place which will never be used :(
}







////// HELPER FUNCTIONS ////////
void connect() {

  WiFi.onEvent(WiFiEvent);
  WiFi.mode(WIFI_STA);
  WiFi.config(local_IP, gateway, subnet);
  WiFi.begin(ssid,password,1,NULL,true); //begin(char* ssid, char *passphrase = NULL, int32_t channel = 0, const uint8_t* bssid = NULL, bool connect = true);
  WiFi.config(local_IP, gateway, subnet);





  while (WiFi.status() != WL_CONNECTED)
  {
    Serial.print(".");
    delay(10);
  }
  Serial.println("connected");
  client.setServer(server, 1883);  //IP of mqtt broker and port - 1883 is default port
  Serial.println(millis());  // time passed since wakeup
}




void checkConnection() {
  if(WiFi.status() != WL_CONNECTED) { // check WiFi
    connect();
  }
  while (!client.connected())  { // check MQTT
    if ( client.connect("client name") ) {

    }
    String tmp = "Device online ";
    tmp += millis();
    char temp[tmp.length() + 1];
    tmp.toCharArray(temp, tmp.length() + 1);


    client.publish("topic/status", temp);

  }
}

void WiFiEvent(WiFiEvent_t event)
{
    Serial.printf("[WiFi-event] event: %d\n", event);
}