#include <ESP8266WiFi.h>
#include <WiFiClient.h>
const char *ssid = "ESPap";
const char *password = "thereisnospoon";
WiFiServer server(8080);
void setup() {
delay(1000);
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);
server.begin();
}
void loop() {
WiFiClient clie = server.available();
if(clie) {
while(clie.connected()) {
if(clie.available()) {
Serial.println(clie.read());
}
}
clie.stop();
}
}
I'm new to IoT. My goal is to start a TCP server using NodeMCU 1.0 to listen to the string sent by an Android app. The Android app is already implemented and 100% working. (Tested using AT commands with an ESP8266-01 module).
But when I upload this code to the NodeMCU it doesn't print out the strings in the Serial Monitor.
What is wrong? There is no errors showing up either.
Did you try using clie.readString() or clie.readStringUntil() instead of clie.read().
Related
I am new to Arduino and I am not so familiar with it. I am not sure why the client cannot connect to the server and I have been looking at it for hours. Any solution to this would be a great help.
So I successfully establish a server with the code below. But...
// server.ino
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
const char* ssid = "WifiName"; // Wifie name
const char* password = "WifiPassword"; // Wifi password
float sensor_value = 0.0;
String Website;
ESP8266WebServer server(80);
void setup(){
Serial.begin(115200);
WiFi.mode(WIFI_AP);
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while(WiFi.status()!=WL_CONNECTED){
Serial.print(".");
delay(500);
}
Serial.println("Server started at port 80.");
Serial.println("WiFi connected.");
Serial.println("IP address: ");
Serial.print("URL=http://");
Serial.println(WiFi.localIP());
server.on("/", handleIndex); //use the top root path report last sensor value
server.on("/update",handleUpdate); // use this route to update sensor value
server.begin();
}
void loop(){
server.handleClient();
}
void handleIndex(){
Website = "<html><body onload ='process()'><div id='div1'>"+ String(sensor_value) +"</div></body></html>";
server.send(200," text/html",Website);
}
void handleUpdate(){
sensor_value = server.arg("value").toFloat();
Serial.println(sensor_value);
server.send(200,"text/plain","Updated");
}
I try to connect a client to the server so it could send data to the server, but a connection between the client and the server cannot be established and I don't know why. I check the IP address and it is all correct I just don't get why the client fails to connect to the server
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <HX711.h>
#include "Wire.h"
#define DOUT D5
#define CLK D6
HX711 scale;
const char* ssid = "WifiName";
const char* password = "Wifipassowrd";
float calibration_factor = 107095;
float val_Weight;
const char* host = "192.168.0.167"; // Server host IP.
const int port = 80;
WiFiClient client;
void setup() {
Serial.begin(115200); //set baud rate
Serial.println("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED)
{
delay(500);//millisecond
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected & connect to client");
}
void loop() {
//connect to the server and send the data as URL parameter
if(client.connect(host, port)){
String url = "update?value=";
url+=String(25.0);
client.print(String("GET /") + url + "HTTP/1.1\r\n" + "Host: " + host + "\r\n" +
"Connection: close\r\n\r\n");
delay(10);
Serial.println("Response: ");
while(client.available()){
String line = client.readStringUntil('\r');
Serial.print(line);
}
}else{
Serial.println("fail");
}
}
Any help would be great thanks!!!
Check the passwords, you have a typo.
const char* password = "Wifipassowrd";
I have been trying to connect my ESP32 with HiveMQ MQTT broker url. It connects when I use free public MQTT broker like broker.hivemq.com, but when I use my url which I got after registering in HiveMQ, it doesn't connect. It returns error with code 2.
I have used this MQTT broker url with windows MQTT client app and it works fine but it doesn't work with ESP32.
#include <WiFi.h>
#include <PubSubClient.h>
// WiFi
const char *ssid = "********"; // Enter your WiFi name
const char *password = "********"; // Enter WiFi password
// MQTT Broker
const char *mqtt_broker = "591c2cacc87d4e248d106212ae6e0d4f.s2.eu.hivemq.cloud";
const char *topic = "esp32/test";
const char *mqtt_username = "*******";
const char *mqtt_password = "*******";
const int mqtt_port = 8883;
WiFiClient espClient;
PubSubClient client(espClient);
void setup() {
// Set software serial baud to 115200;
Serial.begin(115200);
// connecting to a WiFi network
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.println("Connecting to WiFi..");
}
Serial.println("Connected to the WiFi network");
//connecting to a mqtt broker
client.setServer(mqtt_broker, mqtt_port);
client.setCallback(callback);
while (!client.connected()) {
String client_id = "esp32-client-";
client_id += String(WiFi.macAddress());
Serial.printf("The client %s connects to the public mqtt broker\n", client_id.c_str());
if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
Serial.println("Public emqx mqtt broker connected");
} else {
Serial.print("failed with state ");
Serial.print(client.state());
delay(2000);
}
}
// publish and subscribe
client.publish(topic, "Hi EMQ X I'm ESP32 ^^");
client.subscribe(topic);
}
void callback(char *topic, byte *payload, unsigned int length) {
Serial.print("Message arrived in topic: ");
Serial.println(topic);
Serial.print("Message:");
for (int i = 0; i < length; i++) {
Serial.print((char) payload[i]);
}
Serial.println();
Serial.println("-----------------------");
}
void loop() {
client.loop();
}
In the comments, #hcheung said:
When you use MQTT over TLS (port 8883), you need to use WiFiClientSecure.h and add the root CA of broker.hivemq.com to your sketch. Refer to WiFiClientSecure on how to do it.
You can get the root CA of your HiveMQ broker with the following OpenSSL method:
openssl s_client -connect hivemq-broker-host:8883 -showcerts
Change hivemq-broker-host with your MQTT host.
Using a combination of Farhan's example and a few other examples I found elsewhere, I was able to get this to work.
First, open a terminal run the command from Johnny Boy's answer (This assumes you have openssl installed. If not, install it.
openssl s_client -connect YOUR_URL.hivemq.cloud:8883 -showcerts
You'll get three certificates. They look like this
-----BEGIN CERTIFICATE----- MIIFYDCCBEigAwIBAgIQQAF3ITfU6UK47naqPGQKtzANBgkqhkiG9w0BAQsFADA/
MSQwIgYDVQQKExtEaWdpdGFsIFNpZ25hdHVyZSBUcnVzdCBDby4xFzAVBgNVBAMT
DkRTVCBSb290IENBIFgzMB4XDTIxMDEyMDE5MTQwM1oXDTI0MDkzMDE4MTQwM1ow
...Lots more characters that I'll omit for brevity...
-----END CERTIFICATE-----
The third certificate is the one you want. Copy this certificate out of your terminal (including the BEGIN and END CERTIFICATE parts). Paste the cert into your ESP32 code as a const char variable, such as:
const char *ROOT_CERT = "-----BEGIN CERTIFICATE-----\n"
"MIIFYDCCBEigAwIBAgIQQAF3ITfU6UK47naqPGQKtzANBgkqhkiG9w0BAQsFADA/\n"
"MSQwIgYDVQQKExtEaWdpdGFsIFNpZ25hdHVyZSBUcnVzdCBDby4xFzAVBgNVBAMT\n"
... etc..
Using the WiFiClientSecure library mentioned in the comments, use the setCACert function to utilize your certificate. The rest of the code looks pretty close to what Farhan had. In my example, a few of the variables, including the ROOT_CERT variable from above, were defined in another file (WifiCredentials.h):
#include <PubSubClient.h>
#include <WiFi.h>
#include <WiFiClient.h>
#include <WiFiServer.h>
#include <WiFiUdp.h>
#include "WifiCredentials.h"
#include <WiFiClientSecure.h>
*********/
Helpful References:
* https://randomnerdtutorials.com/esp32-web-server-arduino-ide/
*
*********/
WiFiClientSecure wifiClient;
PubSubClient mqttClient(wifiClient);
char *mqttServer = "YOUR_URL.hivemq.cloud";
int mqttPort = 8883;
const char *mqtt_password = "password_I_setup_at_hivemq";
const char *mqtt_username = "username_I-setup_at_hivemq";
void setup() {
Serial.begin(9600);
// Connect to Wi-Fi network
Serial.print("Connecting to ");
Serial.println(WifiSSID);
WiFi.begin(WifiSSID, WifiPassword);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.println("...Still Connecting");
}
Serial.println("");
Serial.println("WiFi connected.");
wifiClient.setCACert(ROOT_CERT);
}
void loop(){
if (!mqttClient.connected()) {
mqttClient.setServer(mqttServer, mqttPort);
// set the callback function
mqttClient.setCallback(callback);
Serial.println("Connecting to MQTT Broker...");
while (!mqttClient.connected()) {
Serial.println("Reconnecting to MQTT Broker..");
String clientId = "ESP32Client-";
clientId += String(random(0xffff), HEX);
if (mqttClient.connect(clientId.c_str(), mqtt_username, mqtt_password)) {
Serial.println("Connected to MQTT BRoker!.");
// subscribe to topic
mqttClient.subscribe("/transactions/device1");
mqttClient.publish("/transactions/device1", "testing hello");
} else {
Serial.print("failed with state ");
Serial.print(mqttClient.state());
delay(2000);
}
}
}
mqttClient.loop();
}
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print("Callback - ");
Serial.print("Message:");
for (int i = 0; i < length; i++) {
Serial.print((char)payload[i]);
}
}
Connect a tool like MQTT Dash to your HiveMQ instance, open a serial monitor, and test your code.
This is the Serial of my arduino it doesn't show anything what am I doing wrong in my code?
Arduino Code
#include <SoftwareSerial.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
const char* host = "WiFi_Robot4_NodeMCU";
const char* ssid = "EarthQuakeBot";
ESP8266WebServer server(80);
void setup() {
IPAddress ip;
Serial.begin(115200);
ip = WiFi.localIP();
Serial.println(ip);
delay(100);
// Connecting WiFi
WiFi.mode(WIFI_AP);
WiFi.softAP(ssid);
// Starting WEB-server
server.on ( "/", HTTP_handleRoot );
server.onNotFound ( HTTP_handleRoot );
server.begin();
}
void loop() {
}
How to display the localIP of nodemcu esp8266 in Serial using Arduino?
The code works without delay, just copy it (SoftwareSerial is commented out and a text line as print support is added, never use the delay with the Esps):
//#include <SoftwareSerial.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
const char* host = "WiFi_Robot4_NodeMCU";
const char* ssid = "EarthQuakeBot";
ESP8266WebServer server(80);
void HTTP_handleRoot() {
// Some code here
}
void setup() {
IPAddress ip;
Serial.begin(115200);
ip = WiFi.localIP();
Serial.print("This is my ip: ");
Serial.println(ip);
// Connecting WiFi
WiFi.mode(WIFI_AP);
WiFi.softAP(ssid);
// Starting WEB-server
server.on ( "/", HTTP_handleRoot );
server.onNotFound ( HTTP_handleRoot );
server.begin();
}
void loop() {
}
and displays (oh wonder) the following:
This is my ip: 0.0.0.0
If using the nodeMCU in AP_Mode (as an access point) you have to assign all the relevant data yourself.Thereis noself assign function, you do it like:
Serial.begin(115200);
.....
WiFi.softAPConfig(apIP, apGateway, apSubnet);
WiFi.mode(WIFI_AP);
WiFi.softAP(ssid);
.........
ip = WiFi.localIP();
Serial.print("This is my ip: ");
Serial.println(ip);
Work through the library examples and follow a good tutorial like:
https://tttapa.github.io/ESP8266/Chap01 - ESP8266.html
Hope this helps you and other beginners
Hi I am new to arduino programming and I am have an issue. I have successfully managed to display the wifi using esp8266 module i.e when I run my code the esp8266 module creates a wifi. It also asks for password but after that there is no output of successful connection. I am using the method wifi.softAp(username,password) for creation of wifi network. I have written the following code:
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
const char* ssid = "Jeet";//Wifi username
const char* password = "wifibin12"; //Wifi password
ESP8266WebServer server(80);
void handleRoot() {
server.send(200, "text/plain", "<h1>hello from esp8266!</h1>");
}
void setup(void) {
// put your setup code here, to run once:
Serial.begin(115200);
//WiFi.mode(WIFI_AP);
Serial.print("this is my pass");
Serial.print(password);
WiFi.softAP(ssid, password);
Serial.print("Setting soft-Ap ... ");
// Wait for connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
//If connection successful show IP address in serial monitor
Serial.println("");
Serial.print("Connected to ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP()); //IP address assigned to your ESP
server.on("/", handleRoot); //Which routine to handle at root location
server.begin(); //Start server
Serial.println("HTTP server started");
}
void loop() {
// put your main code here, to run repeatedly:
server.handleClient();
}
When I run the code I get ............. output continuously on serial monitor. Kindly help me fix this issue if anyone knows what I am doing wrong. Suggestions would also be appreciated.
It's getting stuck to while loop. Wifi.status() returns WL_CONNECTED when it is connected to wifi network (to another Access Point). So if you want just get AP to work you should try this:
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
const char* ssid = "Jeet"; //Wifi username
const char* password = "wifibin12"; //Wifi password
ESP8266WebServer server(80);
void handleRoot() {
server.send(200, "text/plain", "<h1>hello from esp8266!</h1>");
}
void setup(void) {
// put your setup code here, to run once:
Serial.begin(115200);
Serial.print("this is my pass");
Serial.print(password);
WiFi.softAP(ssid, password);
Serial.print("Setting soft-Ap ... ");
// Wait for connection
//If connection successful show IP address in serial monitor
Serial.println("");
Serial.print("AP name ");
Serial.println(ssid);
Serial.print("IP address: ");
Serial.println(WiFi.localIP()); //IP address assigned to your ESP
server.on("/", handleRoot); //Which routine to handle at root location
server.begin(); //Start server
Serial.println("HTTP server started");
}
void loop() {
// put your main code here, to run repeatedly:
server.handleClient();
}
And WiFi.localIP() doesn't return AP's local ip. Default is 192.168.4.1.
I recommend looking docs and examples from here: https://github.com/esp8266/Arduino/tree/master/doc/esp8266wifi
The problem is that I want to execute the code below, but when ESP8266 is shut down, then I start it again, everything is gone.
So, is there a solution that I can make this ESP8266 work the same controlled by my Arduino Uno.
My program blow is to control the GPIO2 through web browser.
Thanks a lot to all of you!!
My Codes:
#include <ESP8266WiFi.h>
#include <aREST.h>
// Create aREST instance
aREST rest = aREST();
// WiFi parameters
const char* ssid = "Protect Big Dragon 4";
const char* password = "18717772056";
// The port to listen for incoming TCP connections
#define LISTEN_PORT 80
// Create an instance of the server
WiFiServer server(LISTEN_PORT);
void setup(void)
{
// Start Serial
Serial.begin(115200);
// Give name and ID to device
rest.set_id("2");
rest.set_name("lamp_control");
// Connect to WiFi
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
// Start the server
server.begin();
Serial.println("Server started");
// Print the IP address
Serial.println(WiFi.localIP());
}
void loop() {
// Handle REST calls
WiFiClient client = server.available();
if (!client) {
return;
}
while(!client.available()){
delay(1);
}
rest.handle(client);
}
So your ESP8266 loses your code when it is rebooted.
Sounds like the memory is faulty.
Try a different ESP8266 and let us know what occurs.