ESP32 Smart Thermostat with TFT Touchscreen

Smart thermostat uses ESP32 with 2.8-inch ILI9341 TFT touchscreen (240x320) and XPT2046 touch controller creating a Nest-like smart thermostat. Current temperature and humidity from DHT22 or BME280. Target temperature set by up/down touch buttons or drag. HVAC control: relay outputs for Heat, Cool, Fan. Safety: minimum on-time 5 minutes to protect compressor. Display: large temperature readout, setpoint, HVAC mode, schedule status. Scheduling: 4 time slots per day, 7 days configurable via web interface. Geo-fencing: phone GPS via IFTTT webhook to detect owner leaving (Away mode) and returning. MQTT integration for Home Assistant. Presence sensor: PIR or mmWave radar to auto-away after 30 minutes no motion. Voice control via Google Assistant / Alexa via Sinric Pro. Libraries: TFT_eSPI, XPT2046_Touchscreen, DHT, PubSubClient, WiFi, NTPClient.

Detailed Project Description

ESP32 Smart Thermostat with TFT Touchscreen focuses on a specific hardware interface or peripheral and shows exactly how to wire it, drive it from firmware and verify it is working.

How It Works
1. The peripheral is connected to the controller using the required bus (SPI/I2C/UART/I2S/CAN/RS-485/PWM/ADC).
2. The driver library is initialised and the peripheral configured.
3. Firmware exchanges data with the peripheral and processes it (measure, decode, render, play).
4. Results are verified on a display, serial monitor or the receiving device.

Key Components and Their Role
- ESP32: dual-core Wi-Fi + Bluetooth microcontroller that runs the firmware, reads the sensors and hosts the network connection.
- DHT22: digital temperature and humidity sensor with better accuracy than DHT11.
- BME280: I2C sensor for temperature, humidity and barometric pressure.
- PIR motion sensor: passive infrared sensor that detects human movement.
- Relay module: electrically isolated switch that lets the controller turn AC/DC loads on and off.
- TFT display: colour graphical display (SPI) used for the on-device user interface.
- GPS module (NEO-6M): receiver that provides latitude, longitude, speed and time over UART/NMEA.
- MQTT: lightweight publish/subscribe messaging protocol used for IoT data.

Implementation Steps
1. Collect the components and study each module's datasheet (pin-out, voltage, interface).
2. Wire the circuit on a breadboard following the pin mapping; power sensors from the correct rail (3.3 V / 5 V).
3. Install Arduino IDE, TFT_eSPI Library, XPT2046 Library and the required libraries; flash a minimal test sketch for each module separately.
4. Write the main firmware: read sensors → process → drive outputs / send data.
5. Configure network or cloud credentials and test communication end-to-end.
6. Calibrate thresholds, add error handling (reconnect, sensor time-out) and run a long-duration test.
7. Finalise on a PCB / enclosure and document wiring, code and results.

Key Features
- Correct wiring and bus configuration
- Driver setup
- Data processing
- Verification on real hardware

Expected Output
On completion the student will have a working peripheral that is measured/driven exactly as intended.

Deliverables
- Complete source code with comments
- Circuit diagram and pin mapping
- Project report with screenshots and results
- Demonstration-ready build