HI there,
ive used MQtt library for Esp8266 it works perfect. its superb easy to understand and easy to implement. so now im trying to use ARDUINO NANO+SIM800L GSM module and i make it work with several other MQTT libraries but i have no idea how to implement it to ubidots. as i have to login ubidots Token to be able to publish something i couldnt make it work in my mind. i`m hoping that Ubidots team can end up with GPRS library implementation for MQTT.
[SOLVED] Gprs mqtt library
MertG
#1
Hello @MertG,
First, I recommend you test the official Arduino GPRS example in order to discard some kind of hardware problem and verify that everything’s okay!
/*
This sketch test the GSM shield's ability to connect to a
GPERS network. It asks for APN information through the
serial monitor and tries to connect to arduino.cc.
Circuit:
* GSM shield attached
* SIM card with data plan
Created 18 Jun 2012
by David del Peral
This example code is part of the public domain
http://www.arduino.cc/en/Tutorial/GSMToolsTestGPRS
*/
// libraries
#include <GSM.h>
// PIN Number
#define PINNUMBER ""
// initialize the library instance
GSM gsmAccess; // GSM access: include a 'true' parameter for debug enabled
GPRS gprsAccess; // GPRS access
GSMClient client; // Client service for TCP connection
// messages for serial monitor response
String oktext = "OK";
String errortext = "ERROR";
// URL and path (for example: arduino.cc)
char url[] = "arduino.cc";
char urlproxy[] = "http://www.arduino.cc";
char path[] = "/";
// variable for save response obtained
String response = "";
// use a proxy
boolean use_proxy = false;
void setup() {
// initialize serial communications and wait for port to open:
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for Leonardo only
}
}
void loop() {
use_proxy = false;
// start GSM shield
// if your SIM has PIN, pass it as a parameter of begin() in quotes
Serial.print("Connecting GSM network...");
if (gsmAccess.begin(PINNUMBER) != GSM_READY) {
Serial.println(errortext);
while (true);
}
Serial.println(oktext);
// read APN introduced by user
char apn[50];
Serial.print("Enter your APN: ");
readSerial(apn);
Serial.println(apn);
// Read APN login introduced by user
char login[50];
Serial.print("Now, enter your login: ");
readSerial(login);
Serial.println(login);
// read APN password introduced by user
char password[20];
Serial.print("Finally, enter your password: ");
readSerial(password);
// attach GPRS
Serial.println("Attaching to GPRS with your APN...");
if (gprsAccess.attachGPRS(apn, login, password) != GPRS_READY) {
Serial.println(errortext);
} else {
Serial.println(oktext);
// read proxy introduced by user
char proxy[100];
Serial.print("If your carrier uses a proxy, enter it, if not press enter: ");
readSerial(proxy);
Serial.println(proxy);
// if user introduced a proxy, asks him for proxy port
int pport;
if (proxy[0] != '\0') {
// read proxy port introduced by user
char proxyport[10];
Serial.print("Enter the proxy port: ");
readSerial(proxyport);
// cast proxy port introduced to integer
pport = (int) proxyport;
use_proxy = true;
Serial.println(proxyport);
}
// connection with arduino.cc and realize HTTP request
Serial.print("Connecting and sending GET request to arduino.cc...");
int res_connect;
// if use a proxy, connect with it
if (use_proxy) {
res_connect = client.connect(proxy, pport);
} else {
res_connect = client.connect(url, 80);
}
if (res_connect) {
// make a HTTP 1.0 GET request (client sends the request)
client.print("GET ");
// if use a proxy, the path is arduino.cc URL
if (use_proxy) {
client.print(urlproxy);
} else {
client.print(path);
}
client.println(" HTTP/1.0");
client.println();
Serial.println(oktext);
} else {
// if you didn't get a connection to the server
Serial.println(errortext);
}
Serial.print("Receiving response...");
boolean test = true;
while (test) {
// if there are incoming bytes available
// from the server, read and check them
if (client.available()) {
char c = client.read();
response += c;
// cast response obtained from string to char array
char responsechar[response.length() + 1];
response.toCharArray(responsechar, response.length() + 1);
// if response includes a "200 OK" substring
if (strstr(responsechar, "200 OK") != NULL) {
Serial.println(oktext);
Serial.println("TEST COMPLETE!");
test = false;
}
}
// if the server's disconnected, stop the client:
if (!client.connected()) {
Serial.println();
Serial.println("disconnecting.");
client.stop();
test = false;
}
}
}
}
/*
Read input serial
*/
int readSerial(char result[]) {
int i = 0;
while (1) {
while (Serial.available() > 0) {
char inChar = Serial.read();
if (inChar == '\n') {
result[i] = '\0';
return 0;
}
if (inChar != '\r') {
result[i] = inChar;
i++;
}
}
}
}
Once you already tested you can use the PubSubClient library for the MQTT communication. At the moment I don’t have an example using GPRS+MQTT, but I’m going to provide you one using a MQTT client and Wi-fi client, you can follow the same structure and integrate the GPRS client instead of the Wi-Fi one.
#include <PubSubClient.h>
#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
#define WIFISSID "...."
#define PASSWORD "...."
#define TOKEN "...."
#define VARIABLE_LABEL "...."
#define DEVICE_LABEL "...."
char mqttBroker[] = "things.ubidots.com";
char payload[100];
char topic[150];
ESP8266WiFiMulti WiFiMulti;
WiFiClient ubidots;
PubSubClient client(ubidots);
void callback(char* topic, byte* payload, unsigned int length) {
char p[length + 1];
memcpy(p, payload, length);
p[length] = NULL;
String message(p);
if (message == "0") {
//digitalWrite(PIN, LOW);
} else {
//digitalWrite(PIN, HIGH);
}
Serial.write(payload, length);
Serial.println(topic);
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.println("Attempting MQTT connection...");
// Attempt to connect
if (client.connect("linkit-one", TOKEN,"")) {
Serial.println("connected");
client.subscribe(TOPIC1);
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 2 seconds");
// Wait 2 seconds before retrying
delay(2000);
}
}
}
void setup() {
Serial.begin(115200);
delay(10);
WiFiMulti.addAP(WIFISSID, PASSWORD);
Serial.println();
Serial.println();
Serial.print("Wait for WiFi... ");
while(WiFiMulti.run() != WL_CONNECTED) {
Serial.print(".");
delay(500);
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
client.setServer(mqttBroker, 1883);
client.setCallback(callback);
}
void loop() {
if (!client.connected()) {
reconnect();
}
sprintf(topic, "%s%s", "/v1.6/devices/", DEVICE_LABEL);
sprintf(payload, "{\"%s\": %s}", VARIABLE_LABEL, "1");
client.publish(topic, payload);
client.loop();
delay(1000);
}
I hope my information would help you!
Regards
Maria C,
MertG
#3
Thanks Maria. i`ve used MQTT WIFI Library and iot works spotless. but i dont know how to replace WIFI with GPRS options. so if you can arrange an example or be more specific in terms of guidence it would be appreciated.
jotathebest
#4
Hi @MertG,
You should declarate an GPRS client instead of a WifiClient and the use the pubsubclient library.
Regards