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Forked from ItKindaWorks/deepSleepDemo.ino
Created August 14, 2017 18:06
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A demo of the deep sleep functionality on ESP8266 devices.
Copyright (c) 2017 ItKindaWorks All right reserved.
This file is part of ESPHelper
ESPHelper is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
ESPHelper is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with ESPHelper. If not, see <>.
#include "ESPHelper.h"
#include "Metro.h"
#include <TimeLib.h>
#include <WiFiUdp.h>
#include <EspProwl.h>
//setup macros for time
#define SECOND 1000L
#define MINUTE SECOND * 60L
#define HOUR MINUTE * 60L
//timers for turn off
Metro minRun = Metro(1 * MINUTE);
Metro maxRun = Metro(5 * MINUTE);
//NTP setup vars
static const char ntpServerName[] = "";
const int timeZone = -5;
WiFiUDP Udp;
unsigned int localPort = 8888; // local port to listen for UDP packets
time_t getNtpTime();
void sendNTPpacket(IPAddress &address);
netInfo homeNet = {.name = "NETWORK NICKNAME", .mqtt = "YOUR MQTT-IP", .ssid = "YOUR SSID", .pass = "YOUR NETWORK PASS"};
ESPHelper myESP(&homeNet);
//hostname for ESPHelper/OTA
char* netHostName = "NEW-ESP8266";
//initDone keeps track of initialization finished or not
bool initDone = false;
//done keeps track of whether the device has finished the task
bool done = false;
void setup() {
// myESP.enableHeartbeat(2); //07 / 12E ledPin
myESP.enableHeartbeat(1); //01 ledPin
void loop(){
if(myESP.loop() == FULL_CONNECTION){
//once we have a full connection trigger some extra setup
//setup the NTP connection and get the current time
//only set initDone to true if the time is set
if(timeStatus() != timeNotSet){
initDone = true;
//if were not done running the code that we need to finish executing and we are done initializing
if(!done && initDone){
//generate a char array to store the data being published
char timeStamp[30];
//fill the array with the time data
createTimeString(timeStamp, 30);
//create a string that will be published
String pubString = String("Mailbox opened at ");
//add the timestamp to the string
pubString += timeStamp;
//convert the string to a char array that can be published/pushed to IOS
char message[50];
pubString.toCharArray(message, 50);
//publish/push the message to IOS
myESP.publish("/test/uptime", message, true);
EspProwl.push("Mailbox ESP8266", message, 0);
done = true;
//send the ESP to deep sleep (to be woken up by pulling rst low)
if((minRun.check() && done) || maxRun.check()){
ESP.deepSleep(0, WAKE_RF_DEFAULT);
void callback(char* topic, uint8_t* payload, unsigned int length) {
//generate a str with the current date/time
void createTimeString(char* buf, int length){
time_t t = now();
String timeString = String(hour(t));
timeString += ":";
timeString += minute(t);
timeString += ":";
timeString += second(t);
timeString += " ";
timeString += month(t);
timeString += "/";
timeString += day(t);
timeString += "/";
timeString += year(t);
timeString.toCharArray(buf, length);
/*-------- NTP code ----------*/
void setupNTP(){
const int NTP_PACKET_SIZE = 48; // NTP time is in the first 48 bytes of message
byte packetBuffer[NTP_PACKET_SIZE]; //buffer to hold incoming & outgoing packets
time_t getNtpTime()
IPAddress ntpServerIP; // NTP server's ip address
while (Udp.parsePacket() > 0) ; // discard any previously received packets
//Serial.println("Transmit NTP Request");
// get a random server from the pool
WiFi.hostByName(ntpServerName, ntpServerIP);
//Serial.print(": ");
uint32_t beginWait = millis();
while (millis() - beginWait < 1500) {
int size = Udp.parsePacket();
if (size >= NTP_PACKET_SIZE) {
//Serial.println("Receive NTP Response");, NTP_PACKET_SIZE); // read packet into the buffer
unsigned long secsSince1900;
// convert four bytes starting at location 40 to a long integer
secsSince1900 = (unsigned long)packetBuffer[40] << 24;
secsSince1900 |= (unsigned long)packetBuffer[41] << 16;
secsSince1900 |= (unsigned long)packetBuffer[42] << 8;
secsSince1900 |= (unsigned long)packetBuffer[43];
return secsSince1900 - 2208988800UL + timeZone * SECS_PER_HOUR;
//Serial.println("No NTP Response :-(");
return 0; // return 0 if unable to get the time
// send an NTP request to the time server at the given address
void sendNTPpacket(IPAddress &address)
// set all bytes in the buffer to 0
memset(packetBuffer, 0, NTP_PACKET_SIZE);
// Initialize values needed to form NTP request
// (see URL above for details on the packets)
packetBuffer[0] = 0b11100011; // LI, Version, Mode
packetBuffer[1] = 0; // Stratum, or type of clock
packetBuffer[2] = 6; // Polling Interval
packetBuffer[3] = 0xEC; // Peer Clock Precision
// 8 bytes of zero for Root Delay & Root Dispersion
packetBuffer[12] = 49;
packetBuffer[13] = 0x4E;
packetBuffer[14] = 49;
packetBuffer[15] = 52;
// all NTP fields have been given values, now
// you can send a packet requesting a timestamp:
Udp.beginPacket(address, 123); //NTP requests are to port 123
Udp.write(packetBuffer, NTP_PACKET_SIZE);
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xrubioj commented Aug 14, 2017

Get Months of Battery Life from an ESP8266!

EDIT: By using ESP.deepSleep(time to sleep or 0); rather than
ESP.deepSleep(time to sleep, WAKE_RF_DEFAULT); the power usage is even lower, like 0.02mA or 22uA!!! The Arduino sketch has been updated to reflect is change.

By putting an ESP8266 into deep sleep mode you can get months (if not years) of battery life on a single charge. In this video I go through how to do this and show you guys all a cool program to send push notifications to your phone at the same time!

Links to the schematics for both regular deep sleep mode as well as internal interrupt based deep sleep
Button Deep Sleep:
Internal Interrupt Deep Sleep:

Link to Arduino Sketch:

Links to the libraries used in this video:

Support the It Kinda Works Patreon (And help keep IKW going!!!):

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My site with even more tutorials is!

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