Created MQTT controlled Display

2020-10-03 13:49:53 -05:00
commit a52b4fd5a8
7 changed files with 279 additions and 0 deletions
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -0,0 +1,151 @@
+/*********
+  Rui Santos
+  Complete project details at https://randomnerdtutorials.com  
+*********/
+
+// I connected SCK to D22 and SDA to D21 - but all I get is a weird pattern - is the dislay broken?
+
+#include <Arduino.h>
+#include <Adafruit_I2CDevice.h> 
+#include <Wire.h>
+#include <Adafruit_GFX.h>
+#include <Adafruit_SSD1306.h>
+#include <WiFi.h>
+#include <PubSubClient.h>
+#include <ArduinoJson.h>
+
+#define SCREEN_WIDTH 128 // OLED display width, in pixels
+#define SCREEN_HEIGHT 64 // OLED display height, in pixels
+
+// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
+Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
+
+// Update these with values suitable for your network.
+
+const char* ssid = "Jnd-Front";
+const char* password = "Paris2016";
+const char* mqtt_server = "mqtt.ddns.kawomi.com";
+
+WiFiClient espClient;
+PubSubClient client(espClient);
+unsigned long lastMsg = 0;
+#define MSG_BUFFER_SIZE	(50)
+char msg[MSG_BUFFER_SIZE];
+
+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());
+
+  display.setCursor(0, 0);
+  display.clearDisplay();
+  display.print("Wifi connected\nIP addres:\n");
+  display.print(WiFi.localIP());
+  display.display();
+  delay(1000);
+}
+
+
+void reconnect() {
+  // Loop until we're reconnected
+  while (!client.connected()) {
+    Serial.print("Attempting MQTT connection...");
+    // Create a random client ID
+    String clientId = "ESP32Client-";
+    clientId += String(random(0xffff), HEX);
+    // Attempt to connect
+    if (client.connect(clientId.c_str())) {
+      Serial.println("MQTT connected");
+      client.publish("OLED", "Connected");
+      client.subscribe("OLED/setText");
+    } else {
+      Serial.print("MQTT failed, rc=");
+      Serial.print(client.state());
+      Serial.println(" try again in 5 seconds");
+      // Wait 5 seconds before retrying
+      delay(5000);
+    }
+  }
+}
+
+void callback(char* topic, byte* payload, unsigned int length) {
+  Serial.print("Message arrived [");
+  Serial.print(topic);
+ 
+  String recBuf="";
+  Serial.print("] ");
+  for (int i = 0; i < length; i++) {
+    recBuf += (char)payload[i];
+  }
+  Serial.println(recBuf);
+
+  StaticJsonDocument<1024> jsonDoc;
+  deserializeJson(jsonDoc,recBuf);
+  const char* theText=jsonDoc["text"];
+  int theSize=jsonDoc["size"];
+
+  display.setCursor(40, 0);
+  display.setTextSize(9);
+  display.print("#");
+  display.display();
+  delay(500);
+
+  display.setCursor(0, 0);
+  display.setTextSize(theSize);
+  display.clearDisplay();
+  display.print(theText);
+  display.display();
+
+}
+
+
+void setup() {
+  Serial.begin(115200);
+
+  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
+    Serial.println(F("SSD1306 allocation failed"));
+    for(;;);
+  }
+  delay(2000);
+  display.clearDisplay();
+ display.display(); 
+
+  display.setTextSize(1);
+  display.setTextColor(WHITE);
+  display.setCursor(0, 0);
+  // Display static text
+  display.println("Line 1 -");
+  display.println("Line 2 --");
+  display.println("Line 3 ---");
+  display.display(); 
+
+  setup_wifi(); 
+  client.setServer(mqtt_server, 1883);
+  client.setCallback(callback);
+}
+
+void loop() {
+  if (!client.connected()) {
+    reconnect();
+  }
+  client.loop();
+}
+