Arduino Touch Screen Calculator using TFT LCD

The Arduino Touch Screen Calculator operates by integrating processing, visual output, and user input into a single compact system centered around an Arduino Uno. The 2.4-inch TFT LCD Touch Shield mounts directly onto the Arduino Uno, establishing connections for both display data and touch detection without requiring complex external wiring. Powered by the SPFD5408, Adafruit GFX, and Adafruit TFTLCD libraries, the Arduino renders a graphical user interface onto the screen, drawing a grid of interactive calculator buttons such as numbers and operators. When a user presses a region of the screen, the resistive touch panel overlaid on the TFT LCD registers a change in electrical resistance coordinates. The Arduino reads these analog touch coordinates, maps them to the corresponding visual button zones defined in the code, and interprets the user's input sequence. Once an operation like addition or multiplication is triggered, the microcontroller processes the arithmetic logic internally and updates the display buffer to render the new result in real time on the LCD screen.