ESP32 Load Cell Digital Kitchen Scale with Tare and Auto-Off

Kitchen scale uses ESP32 with HX711 24-bit ADC and 5kg load cell (strain gauge based). Resolution: 0.1g with 5kg full scale. Display: 1.54-inch SPI TFT shows weight in large font, unit (g/kg/oz/lb), tare status, battery indicator. User interface: 3 push buttons for Tare, Unit Toggle, ON/OFF. Auto-power-off: 2 minutes of no button activity or stable weight. Tare: press button to zero the scale. Multi-ingredient mode: add first ingredient, tare, add second ingredient - scale shows second ingredient weight. Nutritional calculator: web interface where you enter recipe and scale guides through measuring each ingredient by weight. Scale accuracy depends on load cell quality and mounting. Calibration: use known weights (500g, 1kg, 2kg) and adjust calibration factor. HX711 gain: 128x for highest sensitivity. Overload indicator: red LED and alarm beep when > 5.5kg. Battery: 1000mAh LiPo, 8 hours continuous use. Libraries: HX711 by bogde, SPI, TFT_eSPI, esp_sleep.

Detailed Project Description

ESP32 Load Cell Digital Kitchen Scale with Tare and Auto-Off 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.
- TFT display: colour graphical display (SPI) used for the on-device user interface.
- Load cell + HX711: strain-gauge weight sensor with a 24-bit ADC amplifier.
- HX711: 24-bit ADC amplifier for load cells.
- Li-ion battery + charger (TP4056): portable power with charge management.

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, HX711 Library by bogde, TFT_eSPI 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