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+# Azure: IoT Dashboard for ESP32 Telemetry
+#### 23 Sep 2024
+
+1. [Services covered](#services-covered)
+2. [Lab description](#lab-description)
+3. [Prerequisites](#prerequisites)
+4. [Lab steps](#lab-steps)
+5. [Lab files](#lab-files)
+6. [Troubleshooting](#troubleshooting)
+7. [Acknowledgements](#acknowledgements)
+
+## Services covered
+- **Azure IoT Hub** 
+- **Azure IoT Central** 
+
+## Lab description
+
+This lab demonstrates how to collect built-in telemetry from an **ESP32** microcontroller and visualize it using a real-time dashboard in **Azure IoT Central**. Telemetry data includes:
+- Wi-Fi signal strength
+- Free heap memory
+- CPU temperature (mocked)
+- Uptime
+
+The ESP32 will send telemetry to Azure IoT Hub, and Azure IoT Central will be used to build a graphical dashboard for real-time monitoring and analysis.
+
+## Prerequisites
+
+1. **Hardware:**
+   - ESP32 microcontroller
+   - USB cable for programming
+
+2. **Software:**
+   - Arduino IDE with ESP32 board support
+   - Azure IoT SDK (`AzureIoTHub` library)
+   - Internet connection
+
+3. **Azure Setup:**
+   - Azure account with access to **Azure IoT Hub** and **Azure IoT Central**.
+   - Basic knowledge of IoT Hub and device connectivity.
+
+## Lab steps
+
+### 1. Create an Azure IoT Hub
+
+1. Go to the [Azure portal](https://portal.azure.com/).
+2. Click **Create a resource**, search for **IoT Hub**, and click **Create**.
+3. Choose **Free Tier** to avoid costs.
+4. Create a resource group and give the IoT Hub a name (e.g., `ESP32Hub`).
+5. After creation, go to **IoT Hub** > **IoT Devices** and click **+ New** to register a new device.
+6. Save the **device connection string**; you’ll use this in the ESP32 code.
+
+### 2. Code the ESP32 for Sending Telemetry
+
+1. Install the required libraries in **Arduino IDE**:
+   - **Azure IoT SDK for ESP32** (`AzureIoTHub` via Library Manager).
+   - **WiFi Library** (built-in).
+
+2. Use the following code to send Wi-Fi signal strength, free heap memory, CPU temperature, and uptime to Azure IoT Hub:
+
+```cpp
+#include <WiFi.h>
+#include <Esp32MQTTClient.h>
+
+const char* ssid = "your-SSID";
+const char* password = "your-PASSWORD";
+const char* connectionString = "HostName=your-iot-hub.azure-devices.net;DeviceId=your-device-id;SharedAccessKey=your-device-key";
+
+static const char* telemetryMessageTemplate = "{\"wifiSignalStrength\":%d,\"freeHeapMemory\":%d,\"cpuTemperature\":%d,\"uptime\":%d}";
+
+void setup() {
+  Serial.begin(115200);
+  WiFi.begin(ssid, password);
+  while (WiFi.status() != WL_CONNECTED) {
+    delay(1000);
+    Serial.println("Connecting to WiFi...");
+  }
+  Esp32MQTTClient_Init((const uint8_t*)connectionString, true);
+}
+
+void loop() {
+  int wifiSignalStrength = WiFi.RSSI();
+  int freeHeapMemory = ESP.getFreeHeap();
+  int cpuTemperature = (esp_random() % 20) + 50;
+  int uptime = millis() / 1000;
+
+  char telemetryMessage[256];
+  sprintf(telemetryMessage, telemetryMessageTemplate, wifiSignalStrength, freeHeapMemory, cpuTemperature, uptime);
+
+  if (Esp32MQTTClient_SendEvent(telemetryMessage)) {
+    Serial.println("Telemetry sent:");
+    Serial.println(telemetryMessage);
+  } else {
+    Serial.println("Telemetry failed.");
+  }
+
+  delay(5000);
+}
+```
+
+3. Upload the code to your ESP32 and monitor the serial console to ensure it's sending telemetry.
+
+### 3. Set Up Azure IoT Central
+
+1. Go to [Azure IoT Central](https://apps.azureiotcentral.com/) and create a new application using the **Free Tier**.
+2. Under **Device Templates**, create a new template for your ESP32 (e.g., `ESP32-Template`).
+3. Define telemetry fields (`wifiSignalStrength`, `freeHeapMemory`, `cpuTemperature`, `uptime`), set their types to **Number**, and save.
+
+### 4. Connect Your ESP32 Device to IoT Central
+
+1. Under **Devices**, create a new device based on the `ESP32-Template` and copy the **Device Connection String**.
+2. Update the ESP32 connection string in the code if necessary and re-upload the code to the ESP32.
+3. Verify that the device connects and sends telemetry data by checking the **Telemetry** tab for your device in IoT Central.
+
+### 5. Create a Dashboard in IoT Central
+
+1. Navigate to **Dashboards** and create a new dashboard.
+2. Add the following widgets:
+   - **Line Chart** for `wifiSignalStrength` and `cpuTemperature`.
+   - **Gauge** for `freeHeapMemory`.
+   - **Number Widget** for `uptime`.
+3. Save your dashboard and monitor real-time data from the ESP32.
+
+## Lab files
+
+- **ESP32 Telemetry Code**: [ESP32_Azure_Telemetry.ino](#)  
+
+## Troubleshooting
+
+- **Connection Issues**: Ensure that your Wi-Fi credentials are correct and the ESP32 is within range.
+- **Azure IoT Hub Configuration**: Verify that the device connection string matches the one from Azure IoT Hub or IoT Central.
+- **Telemetry Not Appearing**: Check the serial monitor for errors. If telemetry isn’t sent, check the IoT Central **Device** page for any communication issues.
+
+## Acknowledgements