Simple ESP8266 deepsleep example

ESP8266_deepsleep.ino

#include <ESP8266WiFi.h>

const char* ssid     = "#########";
const char* password = "#########";

byte connect_wifi() {
  byte timeout = 0;
  
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.print(".");
    if (timeout++ >= 20) {
      Serial.println("--> ERROR: Wifi commection timeout");
      return 1;
    }
  }
  Serial.println();
  return 0;
}

void setup()
{
  byte ret_code;
  
  WiFi.persistent(false);
  Serial.begin(115200);
  Serial.setDebugOutput(true);
  
  delay(2000);
  
  Serial.println();
  Serial.print("--> Connecting Wifi");
  ret_code = connect_wifi();
  if (ret_code == 0) {
    Serial.println("--> Connected!");
    WiFi.printDiag(Serial);
  }

  Serial.println("--> Disconnecting");
  WiFi.disconnect();
  WiFi.mode(WIFI_OFF);
    
  Serial.println("--> Deep sleep");
  ESP.deepSleep(60 * 1000 * 1000, WAKE_RF_DEFAULT);
  delay(1000);
}

void loop()
{
}