Garage Door Opener Calling by Phone Via Arduino and ASTERISK Behind a FritzBox

Recognizing whether the gate is open or closed. The limit switch on the garage door tells the ARDUINO whether the garage is open or closed.

• When the gate opens, the Arduino calls the gara_auf.php file
• When the gate closes, the Arduino calls the gara_zu.php file

The respective PHP file copies the correct sound file, which ASTERISK then plays.

gara_auf.php:

<?php
system("wget --no-cache --spider http://10.45.0.23/LED=GAON");
copy('/usr/share/asterisk/sounds/garage_Auf_40cent.gsm', '/usr/share/asterisk/sounds/garage_aktuell.gsm');
?>

• The wget call controls an LED in the SmartHome to see, the garage is open (LED=GAON) *
• The copy command copies the sound file "garage_auf_40cent.gsm" (garage is OPEN announcement) as "garage_aktuell.gsm" because ASTERISK ALWAYS plays the file "garage_aktuell.gsm" after picking it up

gara_zu.php:

<?php
system("wget --no-cache --spider http://10.45.0.23/LED=GAOFF");
copy('/usr/share/asterisk/sounds/garage_Zu_40cent.gsm', '/usr/share/asterisk/sounds/garage_aktuell.gsm');
?>

• The wget call controls an LED in the SmartHome to see, the garage is cloes (LED=GAOFF) *
• The copy command copies the sound file "garage_zu_40cent.gsm" (garage is CLOSED announcement) as "garage_aktuell.gsm" because ASTERISK ALWAYS plays the file "garage_aktuell.gsm" after picking it up

To operate the garage, see Step 4 - this is done by ASTERISK's Extensions.conf.

*10.45.0.23 is another self-made SmartHome device. See here: https://www.instructables.com/Smart-Home-Event-Viewer/

• Some Linux machine
• running ASTERISK
• running Apache
• running PHP
• A VOIP-compatible router, with me a FritzBox
• Arduino Nano with an ENC28j60 Module or a Wemos D1
• Powersupply for the microcontroller
• Housing for the Arduino hardware
• 1 5 Volt Relay
• 1 resistor 1 kOhm
• a limit switch on the garage door
• some LAN wiring

ASTERISK must register with the FritzBox. For this I define a telephony device and a phone number with a user and a password.

FritzBox start page --> Telephony devices --> Set up a new device

Telephone (with and without answering machine) --> LAN/WLAN (IP telephone) --> Name for the connection (here ast-pi-user) --> Username and Password --> Assign phone number --> Choose whether the phone should answer all calls or only respond to calls to specific numbers. --> accept all calls --> Apply

Thus, ASTERISK can log on to the FritzBox

We edit the sip.conf (/etc/asterisk/sip.conf) as follows

[general]
port=5060
bindaddr=0.0.0.0
dtmfmode=inband          // IMPORTANT that ASTERISK recognizes and processes the key tones

register=ast-pi-user:XXXX@10.45.0.1/622       // Username and Password as defined in the telephony device in the FritzBox and the IP of the router

[ast-pi-user]
username=ast-pi-user     // Username as defined in the telephony device in the router
secret=XXXX              // Password as defined in the telephony device in the router
type=friend
insecure=port,invite
host=10.45.0.1           // IP-Address of the Router
fromdomain=10.45.0.1     // IP-Address of the Router
fromuser=ast-pi-user     // Username as defined in the telephony device in the router
context=anruf            // The context to be called, more on that later
dtmfmode=inband          // IMPORTANT that ASTERISK recognizes and processes the key tones
allow=ulaw
allow=alaw
allow=gsm

In EXTENSIONS.CONF we define the context that ASTERISK should call after accepting the call.

The sound files must be created as "GSM" files. This can be done at https://convertio.co/de/mp3-gsm/ or any other converter

[anruf]
   // Name of the Context as defined in the sip.conf

exten=>622,1,Answer()  
   // Pick up the phone
exten=>622,n,Background(garage_aktuell)
   // Sound file 1 says "Hello" and whether the garage is currently open or closed

exten=>1234,1,System(wget --no-cache -S http://10.45.0.27/BUTTON)
  // When "1234" was entered on the phone keypad, invoke "wget", more on that later
exten=>1234,2,Playback(coderichtig-ade-brbl)
  // ASTERISK says goodbye
exten=>1234,3,Hangup()
   // ASTERSIK hangs up

exten=>i,1,Hangup()
exten=>i,2,Playback(code-falsch-ade-brbl)
  // If "1234" was NOT entered, Sound File 2 (code-wrong-ade-brbl) says the password was wrong and hangs up

The Arduino Sketch

The Limit-Switch is connected to the digital pins 2 and 3

The Relay is connected to the digital pin 5

The remote IP of the Apache Webserver to process the PHP files is here the 10.45.0.2

#include <UIPEthernet.h>

byte mac[] = {0xDE, 0xAE, 0xBD, 0xEF, 0xFE , 0xED};
IPAddress ip(10, 45, 0, 27);
IPAddress subnet(255,255,0,0);
IPAddress gateway(10,45,0,1);
EthernetServer server(80);

String readString;
String reader = "";
int rel = 5;   // relay pin
int auf = 2;   // Limit-Switch-Pin
int zu = 3;   // Limit-Switch-Pin
int a = 0;
int interval = 10;
int crontimer;
char serverrem[] = "10.45.0.2";   //The IP-Address of the Apache-Machine
volatile int aufzu = 2;
volatile unsigned long alteZeit=0, entprellZeit=1000;
volatile unsigned long aZ=0, eZ=2000;

void setup() {
 Ethernet.begin(mac, ip);
 server.begin();
 Serial.begin(9600);
 pinMode(rel, OUTPUT);
 digitalWrite(rel, HIGH);
 pinMode(auf, INPUT);
 pinMode(zu, INPUT);
 Serial.print("Garagencontroller gestartet");
 Serial.println(aufzu);
}

void loop() {
EthernetClient client = server.available();

if (a == 0 and digitalRead(zu) == LOW) {
if (client.connect("10.45.0.2", 80)) {
 client.println("GET /gara/gara_auf.php"); // When the limit switch switches to "closed", call "gara_auf.php".
 a = 1;
 client.println("Host: 10.45.0.2");
 client.println("Connection: close");
 Serial.println("gara_auf.php aufgerufen");
 client.stop();
 client.println();
}
}

if (a == 1 and digitalRead(auf) == HIGH) {
if (client.connect("10.45.0.2", 80)) {
 client.println("GET /gara/gara_zu.php"); // When the limit switch switches to "open", call "gara_zu.php".
 a = 0;
 client.println("Host: 10.45.0.2");
 client.println("Connection: close");
 Serial.println("gara_zu.php aufgerufen");
 client.println();
 client.stop();
}
}

if (!client) {
 return;
}

while(!client.available()){
 delay(1);
}

String request = client.readStringUntil('\r');
if (client) {
 Serial.println("new client");
 boolean currentLineIsBlank = true;
 while (client.connected()) {
 char c = client.read();
 if (client.available()) {
   if (c == '\n' && currentLineIsBlank) {
     client.println("HTTP/1.1 200 OK");
     client.println("Content-Type: text/html");
     client.println("Connection: close");
     client.println();
     client.println("<!DOCTYPE HTML>");
     client.println("<html>");

     if (request.indexOf("/BUTTON") != -1) { // If the call "http://10.45.0.27/BUTTON" comes, ...
       Serial.println("Vorm Schalten");
       digitalWrite(rel, LOW);              // Turn relay ON
       delay(500);                          // Wait 500 milliseconds
       digitalWrite(rel, HIGH);             // Turn relay OFF
       Serial.println("Nachm Schalten");
       client.println("Garage geschaltet");
     }
     client.println("</html>");
     break;
   }
   if (c == '\n') {
     currentLineIsBlank = true;
   } else if (c != '\r') {
     currentLineIsBlank = false;
     }
   }
 }

delay(1);
client.stop();
Serial.println("client disconnected");
}
}

My php-files (gara_auf.php / gara_zu.php) are located in the subdirectory /gara/ below the html-root of the Apache weserver.

The Arduino code is very easy to adapt if an ESP (e.g. Wemos D1) is to be used for WLAN.