mqtt between esp8266 and arduino with PubSubclient - arduino

I am using ESP8266 with arduino using WiFiEsp library.I want to make MQTT connection with arduino so I use PubSubclient library.i got error:
Attempting MQTT connection...failed, rc=-2 try again in 5 seconds
my code is:
#include <WiFiEsp.h>
#include <WiFiEspClient.h>
#include <WiFiEspUdp.h>
#include "SoftwareSerial.h"
#include <PubSubClient.h>
IPAddress server(212, 72, 74, 21);
char ssid[] = "atmel"; // your network SSID (name)
char pass[] = "bets56789"; // your network password
int status = WL_IDLE_STATUS; // the Wifi radio's status
// Initialize the Ethernet client object
WiFiEspClient espClient;
PubSubClient client(espClient);
SoftwareSerial soft(2,3); // RX, TX
void setup() {
// initialize serial for debugging
Serial.begin(9600);
// initialize serial for ESP module
soft.begin(115200);
// initialize ESP module
WiFi.init(&soft);
// check for the presence of the shield
if (WiFi.status() == WL_NO_SHIELD) {
Serial.println("WiFi shield not present");
// don't continue
while (true);
}
// attempt to connect to WiFi network
while ( status != WL_CONNECTED) {
Serial.print("Attempting to connect to WPA SSID: ");
Serial.println(ssid);
// Connect to WPA/WPA2 network
status = WiFi.begin(ssid, pass);
}
// you're connected now, so print out the data
Serial.println("You're connected to the network");
//delay(2000);
//connect to MQTT server
client.setServer(server, 1883);
client.setCallback(callback);
}
//print any message received for subscribed topic
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i=0;i<length;i++) {
Serial.print((char)payload[i]);
}
Serial.println();
}
void loop() {
// put your main code here, to run repeatedly:
if (!client.connected()) {
reconnect();
}
client.loop();
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Attempt to connect, just a name to identify the client
if (client.connect("arduinoClient")) {
Serial.println("connected");
// Once connected, publish an announcement...
client.publish("outSHADAB","hello world");
// ... and resubscribe
client.subscribe("inShadab");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
I am using ESP8266 with arduino using WiFiEsp library.I want to make MQTT connection with arduino so I use PubSubclient library

I don't think the PubSubClient supports the WiFiEsp as a network layer from an arduino.
While the doc list the ESP8266 I believe this is running the PubSubClient directly on the ESP8266 hardware.

Related

esp 32 with esp now and mqtt connection

i trying to acheive some home automation with esp 32. my project is like following
i have several end points with esp 8266 acting likes slave switches sending Id datas to an esp 32 who is my gateway.
both slaves (esp8266) and master gateway (esp 32, are communicating
with espnow library
the gateway should be connected to an mqtt server ( rasperry pi) who
dispatches automation command depending on endpoint Id.
For now i succesfully have communication between esp8266 slaves and esp 32 gateway
i also have succesfully setted my rasperry pi as mqtt broker with home automation command
But i'm blocked when i need to add wifi connection and mqtt messaging to my ESP 32 gateway
My code on the esp32 gateway is
#include <esp_now.h>
#include <WiFi.h>
#include <PubSubClient.h>
#define LED 2
int myData;
char ssid[] = "my ssid";
char password[] = "mypass";
char mqtt_server[] = "192.168.1.55";
WiFiClient espClient;
PubSubClient MQTTclient(espClient);
void OnDataRecv(const uint8_t * mac, const uint8_t *incomingData, int len) {
memcpy(&myData, incomingData, sizeof(myData));
Serial.print("Bytes received: ");
Serial.println(len);
Serial.print("data: ");
Serial.println(myData);
/*
if(myData == 1){
String reponse="device1";
MQTTclient.publish("homecommand",reponse.c_str());
}
*/
for (int t=0; t<3; t++)
{
digitalWrite(LED,HIGH);
delay(50);
digitalWrite(LED,LOW);
delay(50);
}
}
void MQTTconnect() {
while (!MQTTclient.connected()) {
Serial.print("Attente MQTT connection...");
String clientId = "TestClient-";
clientId += String(random(0xffff), HEX);
// test connexion
if (MQTTclient.connect(clientId.c_str(),"","")) {
Serial.println("connected");
} else { // si echec affichage erreur
Serial.print("ECHEC, rc=");
Serial.print(MQTTclient.state());
Serial.println(" nouvelle tentative dans 5 secondes");
delay(5000);
}
}
}
void setup() {
// Initialize Serial Monitor
Serial.begin(115200);
pinMode(LED,OUTPUT);
// Set device as a Wi-Fi Station
WiFi.mode(WIFI_STA);
// Init ESP-NOW
if (esp_now_init() != ESP_OK) {
Serial.println("Error initializing ESP-NOW");
return;
}
// Once ESPNow is successfully Init, we will register for recv CB to
// get recv packer info
esp_now_register_recv_cb(OnDataRecv);
/*
Serial.println("Connect to Wifi");
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(1000);
Serial.print(".");
}
Serial.println("Connected");
MQTTclient.setServer(mqtt_server, 1883);
if (!MQTTclient.connected()) {
MQTTconnect();
}*/
}
void loop() {
// put your main code here, to run repeatedly:
}
The code works well, when i trigger one of my slaves i receive the message print it in serial an blink 3 times
But when i uncomment the part about connecting to my home router and my mqtt broker i lost the 'On DataRecv' callback
So my question is "Is it possible to have an Esp working as espnow gateway to gather messages and at the same time being connected to my home router for mqtt publishing ?"
If yes i would appreciate some help to implement it.
Thanks a lot.
Swap
WiFi.mode(WIFI_STA);
for
WiFi.mode(WIFI_AP_STA);
re:
https://www.electrosoftcloud.com/en/esp32-wifi-and-esp-now-simultaneously/

two ESP8266 to communicate with udp using WiFiESP.h

guys, i'd like to use esp8266 module and wifiesp.h. I wanna make two esp8266 modules to communicate through udp protocol. To use it, i found udp communication example. But I wonder if the example consist receive codes and send codes. Can you help me to find receive code and send code??
Is there any other send and receive code for UDP protocol??
#include <WiFiEsp.h>
#include <WiFiEspUdp.h>
// Emulate Serial1 on pins 6/7 if not present
#ifndef HAVE_HWSERIAL1
#include "SoftwareSerial.h"
SoftwareSerial Serial1(6, 7); // RX, TX
#endif
char ssid[] = "Twim"; // your network SSID (name)
char pass[] = "12345678"; // your network password
int status = WL_IDLE_STATUS; // the Wifi radio's status
unsigned int localPort = 10002; // local port to listen on
char packetBuffer[255]; // buffer to hold incoming packet
char ReplyBuffer[] = "ACK"; // a string to send back
WiFiEspUDP Udp;
void setup() {
// initialize serial for debugging
Serial.begin(115200);
// initialize serial for ESP module
Serial1.begin(9600);
// initialize ESP module
WiFi.init(&Serial1);
// check for the presence of the shield:
if (WiFi.status() == WL_NO_SHIELD) {
Serial.println("WiFi shield not present");
// don't continue:
while (true);
}
// attempt to connect to WiFi network
while ( status != WL_CONNECTED) {
Serial.print("Attempting to connect to WPA SSID: ");
Serial.println(ssid);
// Connect to WPA/WPA2 network
status = WiFi.begin(ssid, pass);
}
Serial.println("Connected to wifi");
printWifiStatus();
Serial.println("\nStarting connection to server...");
// if you get a connection, report back via serial:
Udp.begin(localPort);
Serial.print("Listening on port ");
Serial.println(localPort);
}
void loop() {
// if there's data available, read a packet
int packetSize = Udp.parsePacket();
if (packetSize) {
Serial.print("Received packet of size ");
Serial.println(packetSize);
Serial.print("From ");
IPAddress remoteIp = Udp.remoteIP();
Serial.print(remoteIp);
Serial.print(", port ");
Serial.println(Udp.remotePort());
// read the packet into packetBufffer
int len = Udp.read(packetBuffer, 255);
if (len > 0) {
packetBuffer[len] = 0;
}
Serial.println("Contents:");
Serial.println(packetBuffer);
// send a reply, to the IP address and port that sent us the packet we received
Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());
Udp.write(ReplyBuffer);
Udp.endPacket();
}
}
void printWifiStatus() {
// print the SSID of the network you're attached to:
Serial.print("SSID: ");
Serial.println(WiFi.SSID());
// print your WiFi shield's IP address:
IPAddress ip = WiFi.localIP();
Serial.print("IP Address: ");
Serial.println(ip);
// print the received signal strength:
long rssi = WiFi.RSSI();
Serial.print("signal strength (RSSI):");
Serial.print(rssi);
Serial.println(" dBm");
}

ESP32 access point

I have 2 ESP32 boards, and I want to make them server/client in Arduino IDE. Just two boards, no router in between.
So far I have followed tutorials, and I have been able to connect to the ESP32 from my phone.
#include <WiFi.h>
WiFiServer server;
const char *ssid = "Zupa";
const char *password = "12345678";
void setup() {
Serial.begin(115200);
Serial.println();
Serial.print("Configuring access point...");
WiFi.softAP(ssid, password);
IPAddress myIP = WiFi.softAPIP();
Serial.print("AP IP address: ");
Serial.println(myIP);
}
void loop() {
}
However, I cannot connect from other ESP32. Code as follows:
#include <WiFi.h>
#include <WiFiMulti.h>
WiFiMulti WiFiMulti;
void setup()
{
Serial.begin(115200);
delay(10);
enter code here
// We start by connecting to a WiFi network
WiFiMulti.addAP("Zupa", "12345678");
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());
delay(500);
}
void loop()
{
const uint16_t port = 80;
const char * host = "192.168.1.4"; // ip
Serial.print("connecting to ");
Serial.println(host);
// Use WiFiClient class to create TCP connections
WiFiClient client;
if (!client.connect(host, port)) {
Serial.println("connection failed");
Serial.println("wait 5 sec...");
delay(5000);
return;
}
// This will send the request to the server
client.print("Send this data to server");
//read back one line from server
String line = client.readStringUntil('\r');
client.println(line);
Serial.println("closing connection");
client.stop();
Serial.println("wait 5 sec...");
delay(5000);
}
What happens is it just says it cannot connect. The IP address is default, and I double checked it on the server side! How come I can connect from phone and not from ESP32?
Furthermore, how would I communicate between the two? I tried reading online, but everyone seems to do phone to ESP communication, not ESP to ESP. I also tried reading Mr. Kolbans book on ESP32, but with no success. I am quite new at this, and feel stuck.
All I had to change was the WiFi library from the ESP8266wifi.h to the Wifi.h which is compatible with ESP32.
(Source)
From the code examples is just a matter of changing the code to fit your specific needs.
#include <WiFi.h>
#include <WiFiClient.h>
void setup()
{
Serial.begin(115200);
delay(10);
// We start by connecting to a WiFi network
WiFi.mode(WIFI_STA); //Set wifi mode as station
WiFi.begin("Zupa", "12345678");//Connect to other ESP32
Serial.println();
Serial.println();
Serial.print("Wait for WiFi... ");
//Wait for WiFi to connect
while(WiFi.waitForConnectResult() != WL_CONNECTED){
Serial.print(".");
delay(1000);
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
delay(500);
}
void loop()
{
const uint16_t port = 80;
const char * host = "192.168.1.4"; // ip
Serial.print("connecting to ");
Serial.println(host);
// Use WiFiClient class to create TCP connections
WiFiClient client;
if (!client.connect(host, port)) {
Serial.println("connection failed");
Serial.println("wait 5 sec...");
delay(5000);
return;
}
// This will send the request to the server
client.print("Send this data to server");
//read back one line from server
String line = client.readStringUntil('\r');
client.println(line);
Serial.println("closing connection");
client.stop();
Serial.println("wait 5 sec...");
delay(5000);
}
Try change the IP of client code to:
const char * host = "192.168.4.1"
Tip: I use the Finger app in Android or iOS to scan the network,
its very good to see the IP of each device connected.
(In your case, You need connect the mobile device into your Esp32's hot spot before use the Finger)

NodeMCU gets strange IP address

Today I got my NodeMCU and I instantly started with coding. I wanted to connect to my WiFi and to my MQTT server.
I used the PubSub example for this.
In the serial monitor I get the message that I connected successfully with the WiFi, but I get the IP 172.20.10.6. However we have a 192.168... network.
Then when I try to reach my MQTT server it doesn't find it. When I try to give the NodeMCU a static IP it also says connected successfully and shows up the static IP I gave it, but I still can't connect to my MQTT server.
I can't ping the NodeMCU and don't find it in my Smartphone app "Fing".
#include <ESP8266WiFi.h>
#include <PubSubClient.h>
const char* ssid = "myssid";
const char* password = "mypw";
const char* mqtt_server = "192.168.42.131";
WiFiClient espClient;
PubSubClient client(espClient);
long lastMsg = 0;
char msg[50];
int value = 0;
void setup() {
pinMode(BUILTIN_LED, OUTPUT);
// Initialize the BUILTIN_LED pin as an output
Serial.begin(115200);
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
void setup_wifi() {
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i = 0; i < length; i++) {
Serial.print((char)payload[i]);
}
Serial.println();
// Switch on the LED if an 1 was received as first character
if ((char)payload[0] == '1') {
digitalWrite(BUILTIN_LED, LOW);
// Turn the LED on (Note that LOW is the voltage level
// but actually the LED is on; this is because
// it is active low on the ESP-01)
} else {
digitalWrite(BUILTIN_LED, HIGH);
// Turn the LED off by making the voltage HIGH
}
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Attempt to connect
if (client.connect("ESP8266Client")) {
Serial.println("connected");
// Once connected, publish an announcement...
//client.publish("outTopic", "hello world");
// ... and resubscribe
client.subscribe("mathistest");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
long now = millis();
if (now - lastMsg > 2000) {
lastMsg = now;
++value;
snprintf (msg, 75, "hello world #%ld", value);
}
}
You are most likely having a DHCP failure.
A 172.20.x.x address is a non-routable IP address (see: https://www.lifewire.com/what-is-a-private-ip-address-2625970) and the DHCP code is (likely) using that address when the address assignment fails.
Stepping back, DHCP is most likely failing because you are failing to connect to the Wifi network with the correct SSID and password.

Not able to Receive subscribed Message with PubSubClient.h in Arduino Uno R3

#include "SPI.h"
#include “WiFiEsp.h”
#include <WiFiEspClient.h>
#include “SoftwareSerial.h”
#include <PubSubClient.h>
#include <WiFiEspUdp.h>
float temp=0;
int tempPin = 0;
int isClientConnected = 0;
char data[80];
char ssid[] = “SSID”; // your network SSID (name)
char pass[] = “PASSWORD”; // your network password
int status = WL_IDLE_STATUS; // the Wifi radio’s status
char deviceName = “ArduinoClient1”;
IPAddress server(xxx,xxx,xxx,xxx); //MQTT server IP
IPAddress ip(192,168,43,200);
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print(“Message arrived [“);
Serial.print(topic);
Serial.print(“] “);
for (int i=0;i<length;i++) {
Serial.print((char)payload[i]);
}
Serial.println("-");
}
// Emulate Serial1 on pins 6/7 if not present
WiFiEspClient espClient;
PubSubClient client(espClient);
SoftwareSerial Serial1(6,7); // RX, TX
void setup(){
Serial.begin(9600);
Serial1.begin(9600);
WiFi.init(&Serial1);
WiFi.config(ip);
if (WiFi.status() == WL_NO_SHIELD) {
Serial.println("WiFi shield not present");
while (true);
}
while ( status != WL_CONNECTED) {
Serial.print("Attemptingonnect to WPA SSID: ");
Serial.println(ssid);
status = WiFi.begin(ssid, pass);
Serial.print("WiFius : ");
Serial.println(status);
}
//connect to MQTT server
client.setServer(server, 1883);
client.setCallback(callback);
isClientConnected = client.connect(deviceName);
Serial.println("+++++++");
Serial.print("isClientConnected;
Serial.println(isClientConnected);
Serial.print("client.state");
Serial.println(client.state());
if (isClientConnected) {
Serial.println("Connected…..");
client.publish("status","Welcome to ISG");
client.subscribe("isg/demoPublish/rpi/ardTempWarn");
//Not able to recieve for this subscribed topic on Arduino Uno Only if I
//print it returns 1
}
}
void loop() {
temp = (5.0 * analogRead(tempPin) * 100.0) / 1024;
Serial.print(" temp : " );
Serial.println(temp);
Serial.print("client.connected);
Serial.println(client.connected());
if (!client.connected()) {
reconnect();
}
client.publish("isg/demoPublish/ard1/tempLM35",String(temp).c_str());
// able to receive data at other
// clients like RPI,Web using Mosquitto broker
client.loop();
delay(5000);
}
void reconnect() {
Serial.println("Device is trying to connect to server ");
while (!client.connected()) {
if (client.connect(deviceName)) {
} else {
delay(5000);
}
}
}
I am using Arduino Uno R3 and ESP8266-01 as wifi connector.
I have to read temperature data and send to Mosquitto ,MongoDB and Raspberry Pi and receive a data on specific condition for that i have subscribed a topic in Arduino.
I am able to receive data from Arduino to all other clients but I am not able to receive data on Subscribed topic in Arduino. But all other deviced like MongoDB able to receive data from Raspberry Pi.
I have used Arduino Uno R3, ESP8266-01 devices and liberary for to connect and send/receive data WiFiEsp.h, WiFiEspClient.h, WiFiEspUdp.h, SoftwareSerial.h, PubSubClient.h
client.subscribe("topic"); returns 1
Also callback function implemented but not able to get call.
So can any one help me why I am not getting subscribed topic message in Arduino?
I have follow https://sonyarouje.com/2016/03/15/mqtt-communication-with-arduino-using-esp8266-esp-01/#comment-111773
The library that you are using has bug in callback hence it would be better that you use other library my preference would be
https://github.com/vshymanskyy/TinyGSM
this library include almost all variants of SIM800(A,C,L,H,808), variants of SIM900(A,D,908,968), ESP8266 (mounted on arduino), Ethernet shield etc. It worked for me, as same issue bugged me for almost 1-2 weeks but latter was able to receive all subscribed message irrespective of mode of communication(GSM,Ethernet,WiFi)

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