For an index to all my stories click this text.
This is another entry in my series on using Telegram for IOT purposes.
The first story showed how to get a Telegram account, make a bot and have your ESP connected so you can send commands from Telegram to the ESP to set lamps (etc) on or off. Read that story here cause the program shown there is the base for all consecutive stories.
http://lucstechblog.blogspot.com/2023/01/telegram-messenger-for-iot.html
The second story showed how to use Telegram on your PC next to your Android Phone. This is for home purposes more convenient as you can work on a big screen. For on the road the smartphone version is king. Read that story here: http://lucstechblog.blogspot.com/2023/02/convenient-working-with-telegram.html
The third story showed how to send commands to Telegram for getting sensor readings from your ESP back. The program shown in this story is the base version from the first story with additions to do sensor readings. Read that story here: http://lucstechblog.blogspot.com/2023/02/request-esp-sensor-data-with-telegram.html
This story adds an important thing: notifications. In the previous versions Telegram had to send a command to the ESP to get the readings from your sensors. This story shows how your ESP can send notifications to Telegram. So when a sensor reaches a critical value (temperature to high or low, door open, movemenet detected etc) the ESP will send a warning to Telegram.
Setting up Telegram.
Well I presume you have an account and have already added a bot in Telegram. If not do that first. You can read how to do that in the first story in this series: http://lucstechblog.blogspot.com/2023/01/telegram-messenger-for-iot.html
And because we have to copy some information out of Telegram into the ESP's program it is much easier to work on your computer screen as it is to work on your phone. So start telegram on your PC. If you do not know how to do that read this story first: http://lucstechblog.blogspot.com/2023/02/convenient-working-with-telegram.html
The first thing to do is to get the ID of our bot. You can do that with IDBot a special bot in Telegram that gets the ID.
In Telegram search for IDBot. You will get multiple entries but use the first, the one with the blue logo with the fingerprint in it.
Click on this bot and it will activate and shows the start message. Just click on Begin.
The Bot will be added to your Telegram account.
Just as with your own bot /start will show which commands you can use. We are going to use /getid.
And there is is. I painted it red because I do not want you all to send commands to my bot ;) So keep this ID to yourself just like the Telegram token. Then nobody except yourself can access your home automation system.
You will need this ID and your Telegram token for the next steps.
Breadboard test testup
You can use the same test setup on a breadboard as I published in this story: http://lucstechblog.blogspot.com/2023/02/request-esp-sensor-data-with-telegram.html
However for a quick test just a button is sufficient. Attach the button with a pull-up resistor to GPIO14 if you have a Doit Dev Kit board like I have. Otherwise choose a pin to your liking. Just be carefull: not all IO pins will work when using wifi.
Sending a message to your Bot.
There is a Telegram API to send messages to your bot.
https://api.telegram.org/bot<TOKEN>/sendMessage?chat_id=<CHAT_ID>&text=Just%20a%20test
You can try this in your browser. Just replace <TOKEN> with your token and <CHAT-ID> with the chat ID you just got and hit enter. The message should appear in Telegram. You can alter the text to your liking as long as you remember to replace spaces with %20.
ESP program
You can use the next test program with the ESP8266 and the ESP32. The version I am presenting here is for the ESP32 but can be used with the ESP8266 with some minor alterations.
/* Luc Volders http://lucstechblog.blogspot.com/ */ #include <WiFi.h> #include <HTTPClient.h> const char* ssid = "ROUTERS NAME"; const char* pass = "PASSWORD"; String text; void setup() { // initialize the Serial Serial.begin(115200); Serial.println("Starting..."); WiFi.begin(ssid, pass); delay(500); while (WiFi.status() != WL_CONNECTED) { Serial.print('.'); delay(500); pinMode(14, INPUT); } } void loop() { if ((digitalRead(14))==0) { Serial.println("PRESSED"); HTTPClient http; text = "https://api.telegram.org"; text +="/bot"; text += "YOUR TELEGRAM TOKEN"; text +="/sendMessage?chat_id=YOUR ID"; text +="&text=Button pressed"; http.begin(text); int httpCode = http.GET(); //Send the request if (httpCode > 0) { //Check the returning code String payload = http.getString(); //Get the request response payload Serial.println(payload); //Print the response payload } http.end(); //Close connection } }
Nothing special in this program. Just fill in your routersname and password and at the bottom in the loop fill in your Telegram Token and ID.
To alter the prograqm for the ESP8266 just alter
#include <WiFi.h>
#include <HTTPClient.h>
into
#include <ESP8266WiFi.h>
#include <ESP8266HTTPClient.h>
and in the setup alter
pinMode(14, INPUT);
into
pinMode(12, INPUT);
And the last alteration is
if ((digitalRead(14))==0)
into
if ((digitalRead(12))==0)
And do not forget to attach the button to D5 (pin12).
Before you go to the next step, test this thoroughly. If you press the button a few moments later you will get a notification from Telegram on your phone.
Combining it all.
Maybe you have a seperate ESP-01 on which you want to put the previous program for example a door-bell alarm. However most of the time you will have multiple sensors on your ESP. So therefore I am showing you here the combined program for sending commands and getting notifications on Telegram.
/* Name: Telegram sensor readings Library and demo Author: Tolentino Cotesta <cotestatnt@yahoo.com> Adapted by: Luc Volders http://lucstechblog.blogspot.com/ */ #include <Arduino.h> #include "AsyncTelegram.h" //#include <WiFi.h> #include <HTTPClient.h> #include <DallasTemperature.h> #include <OneWire.h> # define ONE_WIRE_BUS 23 OneWire oneWire(ONE_WIRE_BUS); AsyncTelegram myBot; DallasTemperature dallas(&oneWire); float temp = 0; int button = 34; String tosend = ""; String text; const char* ssid = "YOUR ROUTERS NAME$"; const char* pass = "ROUTER PASSWORD"; const char* token = "TELEGRAM TOKEN"; int led = LED_BUILTIN; void setup() { // initialize the Serial Serial.begin(115200); Serial.println("Starting TelegramBot..."); WiFi.setAutoConnect(true); WiFi.mode(WIFI_STA); WiFi.begin(ssid, pass); delay(500); while (WiFi.status() != WL_CONNECTED) { Serial.print('.'); delay(500); } myBot.setUpdateTime(1000); myBot.setTelegramToken(token); Serial.print("\nTest Telegram connection... "); myBot.begin() ? Serial.println("OK") : Serial.println("NOK"); dallas.begin(); pinMode(led, OUTPUT); digitalWrite(led, LOW); //<== high for esp8266 pinMode(14, INPUT); } void loop() { TBMessage msg; if (myBot.getNewMessage(msg)) { if (msg.text.equalsIgnoreCase("Lon")) { digitalWrite(led, HIGH); //<== low for esp8266 myBot.sendMessage(msg, "Light is now ON"); } else if (msg.text.equalsIgnoreCase("Loff")) { digitalWrite(led, LOW); //<== high for ESP8266 myBot.sendMessage(msg, "Light is now OFF"); } else if (msg.text.equalsIgnoreCase("Temp")) { dallas.requestTemperatures(); Serial.print("Temperature is: "); temp=dallas.getTempCByIndex(0); Serial.println(String(temp)); tosend = "The temperature is now : "; tosend += String(temp); myBot.sendMessage(msg, tosend); } else if (msg.text.equalsIgnoreCase("LDR")) { Serial.print("The LDR's value is: "); Serial.println(analogRead(15)); tosend = "The LDR's value is : "; tosend += String(analogRead(32)); myBot.sendMessage(msg, tosend); } else { // generate the message for the sender String reply; reply = "Welcome ESP8266 number 1\n" ; reply += "You can use these commands :\n" ; reply += "============================\n\n" ; reply += ". Mancave Light on = Lon\n"; reply += ". Mancave Light off = Loff\n\n"; reply += ". What is the temperature = Temp\n"; reply += ". The light value = LDR\n"; myBot.sendMessage(msg, reply); } } if ((digitalRead(14))==0) { Serial.println("PRESSED"); HTTPClient http; text = "https://api.telegram.org"; text +="/bot"; text += token; text +="/sendMessage?chat_id=YOUR ID"; text +="&text=Button pressed"; http.begin(text); int httpCode = http.GET(); //Send the request if (httpCode > 0) { //Check the returning code String payload = http.getString(); //Get the request response payload Serial.println(payload); //Print the response payload } http.end(); //Close connection } }
As you can see it is just the program from the first story in this series combined with the above program. Again this version is for the ESP32 but adapting it for the ESP8266 should prove easy when you followed all the stories in this series.
In the original program the Telegram Bot had a button entry in which you could ask the ESP for the state of the button (pressed or not). I left that out of this version because the button has now a different function.
If you need to test for the state of a switch or other sensor just put it in again and attach that sensor to another pin on your ESP.
Bye Bye IFTTT
I used to use IFTTT for getting alerts on my phone and for other tasks. However IFTTT only alows you to make 3 custom applets for a free account. As I want/need more as 3 custom aplets I have 2 choices. Make a universal applet for IFTTT, something I am tinking about or use Telegram as my all in one chat and IOT console. For now I opt for the last choice.
Domoticz ????
There is one thing left to do. I use Domoticz for my home automation. For commanding Domoticz from my Phone there are two options. There is a Domoticz app in Googles Play store and I have made my own dedicated app.
Domoticz can send notifications to my Telegram bot about my lights, temperature etc. But I can not command my lights from Telegram with my phone. Or can I ??? Stay tuned and I will show you how to do that in an upcoming story.
Till next time
Have fun
Luc Volders