This project presents a secure, low-cost electronic voting system using Arduino Uno, an R305 fingerprint sensor, a keypad-based button interface, and an LCD display. Voters authenticate via ...

If you need to drive a big screen for a project, it’s fair to say your first thought isn’t going to be to use the ATtiny85.

A standard telephone keypad, with four rows of three keys each. The top row consists of 1, 2, and 3, with keys continuing down in order until the last row, which is usually *, 0, and #. Such a keypad ...

Arduino library for the I2C LCD display, typical 20x4 characters. The library is inspired by the excellent New-LiquidCrystal library by F. Malpartida. Therefore the interface is kept quite identical, ...

The voltages and signal timings described below are dependent on the battery voltage and are probably also impacted by temperature. While the calculator runs on a 9 V battery, internally the logic ...