/*
Basic ESP8266 MQTT example
This sketch demonstrates the capabilities of the pubsub library in combination
with the ESP8266 board/library.
It connects to an MQTT server then:
- publishes "hello world" to the topic "outTopic" every two seconds
- subscribes to the topic "inTopic", printing out any messages
it receives. NB - it assumes the received payloads are strings not binary
- If the first character of the topic "inTopic" is an 1, switch ON the ESP Led,
else switch it off
It will reconnect to the server if the connection is lost using a blocking
reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to
achieve the same result without blocking the main loop.
To install the ESP8266 board, (using Arduino 1.6.4+):
- Add the following 3rd party board manager under "File -&nbgt; Preferences -&nbgt; Additional Boards Manager URLs":
http://arduino.esp8266.com/stable/package_esp8266com_index.json
- Open the "Tools -&nbgt; Board -&nbgt; Board Manager" and click install for the ESP8266"
- Select your ESP8266 in "Tools -&nbgt; Board"
*/
#include &nblt;WiFi.h&nbgt;
#include &nblt;PubSubClient.h&nbgt;
#include &nblt;EasyButton.h&nbgt;
#define LED 2 //built-in LED on ESP32
// Update these with values suitable for your network.
const char *ssid = "Stonez24";
const char *password = "a0101010101a";
// Define your client ID on EMQX
String mqtt_ClientID = "stonez56_IOT_Station_";
// Define your topics to subscribe / publish
const char* sub_topic = "stonez56/esp32s";
const char* pub_led_topic = "stonez56/esp32s_led_state";
const char* pub_init_topic = "stonez56/esp32s_is_back";
// EMQX broker parameters
const char *mqtt_server = "broker.emqx.io";
const char *mqtt_userName = "emqx";
const char *mqtt_password = "public";
WiFiClient espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;
#define MSG_BUFFER_SIZE (50)
char msg[MSG_BUFFER_SIZE];
int value = 0;
void setup_wifi()
{
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(".");
}
randomSeed(micros());
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 &nblt; length; i++)
{
Serial.print((char)payload[i]);
}
Serial.println();
payload[length] = '\0';
String message = (char *)payload;
if (strcmp(topic, sub_topic) == 0)
{
if (message == "off")
{
digitalWrite(LED, LOW); //Turn off
client.publish(pub_led_topic, "LED off");
}
if (message == "on")
{
digitalWrite(LED, HIGH); //Turn on
client.publish(pub_led_topic, "LED on");
}
if (message == "flash")
{
digitalWrite(LED, LOW); //LED flashing 2 times
delay(200);
digitalWrite(LED, HIGH);
delay(200);
digitalWrite(LED, LOW);
delay(200);
digitalWrite(LED, HIGH);
delay(200);
digitalWrite(LED, LOW);
client.publish(pub_led_topic, "LED flashed 2 times");
}
}
/* 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.println("Attempting EMQX MQTT connection...");
// Create a random client ID
mqtt_ClientID += String(random(0xffff), HEX);
// Attempt to connect
if (client.connect((mqtt_ClientID, mqtt_userName, mqtt_password)))
{
Serial.print(" connected with Client ID: ");
Serial.println(mqtt_ClientID);
// Once connected, publish an announcement...
client.publish(pub_init_topic, "Hi, I'm online!");
// ... and resubscribe
client.subscribe(sub_topic);
}
else
{
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
void setup()
{
pinMode(LED, OUTPUT); // Initialize the _LED pin as an output
digitalWrite(LED, LOW); //default ESP32 LOW is turn off
Serial.begin(115200);
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
void loop()
{
if (!client.connected())
{
reconnect();
}
client.loop();
/* unsigned long now = millis();
// if (now - lastMsg &nbgt; 2000)
// {
// lastMsg = now;
// ++value;
// snprintf(msg, MSG_BUFFER_SIZE, "hello world #%ld", value);
// Serial.print("Publish message: ");
// Serial.println(msg);
// client.publish("stonez56/esp32s_button_pushed", msg);
// } */
}
modify in the library directory your_directory/Arduino/libraries/ESPAsyncWebServer-master/src/WebAuthentication.cpp @line 72 with this (the comment are the old line ......)
When I tried to compile ESPAsyncWebServer with AsyncElegantOTA, the following error occured:
c:/users/stone/appdata/local/arduino15/packages/esp32/tools/xtensa-esp32-elf-gcc/gcc8_4_0-esp-2021r2-patch3/bin/../lib/gcc/xtensa-esp32-elf/8.4.0/../../../../xtensa-esp32-elf/bin/ld.exe: d:\stone\Documents\build\libraries\ESPAsyncWebServer-master\WebAuthentication.cpp.o:(.literal._ZL6getMD5PhtPc+0x4): undefined reference to `mbedtls_md5_starts'
It looked like the ESPAsyncWebsrver issue, so I went to GitHub to re-download ESPAsyncWebServer (https://github.com/me-no-dev/ESPAsyncWebServer ) and then updated the library. However, this didn't solve the issue that the same error still stopping me from compile it for my ESP32.
After couple of hours, I realized that this was an error that didn't have a proper fixed yet. However, someone at Github provided a solution and it worked for me:
In line 72 of the WebAuthentication.cpp file:
modify in the library directory your_directory/Arduino/libraries/ESPAsyncWebServer-master/src/WebAuthentication.cpp @line 72 with this (the comment are the old line ......)
Just comment these red in comment below and add the blue codes, then compile went fine without issues!