How to ESP32 recieve data form Ubidot to show on Dot Matrix

This code can recieve data form Ubidots

But I don’t know how show data on Dot matrix (MD_MAX72xx)

Plese help me bro.


#include <WiFi.h>
#include <PubSubClient.h>

#define WIFISSID “xxxxxx”

#define PASSWORD “xxxxxx”

#define TOKEN “xxxxxx”

#define MQTT_CLIENT_NAME “Put_your_MQTT_client_name_here”

#define VARIABLE_LABEL_SUBSCRIBE “xxxxxx”

#define DEVICE_LABEL “xxxxxx”

#define RELAY 16

char mqttBroker = “industrial.api.ubidots.com”;

char payload[100];

char topic[150];

char topicSubscribe[100];

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(RELAY, LOW);

} else {

digitalWrite(RELAY, HIGH);
}

Serial.write(payload, length);

Serial.println();
}

void reconnect() {

// Loop until we’re reconnected

while (!client.connected()) {

Serial.println(“Attempting MQTT connection…”);

// Attemp to connect

if (client.connect(MQTT_CLIENT_NAME, TOKEN, “”)) {
Serial.println(“Connected”);

client.subscribe(topicSubscribe);

} else {

Serial.print(“Failed, rc=”);

Serial.print(client.state());

Serial.println(" try again in 2 seconds");

// Wait 2 seconds before retrying

delay(2000);
}
}
}

/****************************************

  • Main Functions
    ****************************************/

void setup() {

Serial.begin(115200);

WiFi.begin(WIFISSID, PASSWORD);

// Assign the pin as OUTPUT

pinMode(RELAY, OUTPUT);

Serial.println();

Serial.print(“Wait for WiFi…”);

while (WiFi.status() != 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);

sprintf(topicSubscribe, “/v1.6/devices/%s/%s/lv”, DEVICE_LABEL, VARIABLE_LABEL_SUBSCRIBE);

client.subscribe(topicSubscribe);
}

void loop() {

if (!client.connected()) {

reconnect();

client.subscribe(topicSubscribe);
}
client.loop();
}

getting help will much more efficient if you follow this

Start with 6. Getting help on the forum

best regards Stefan