The project involves coming up with a mask dispensing system that alerts a person when they exit their home. With an added function of alerting the person when the number of masks runs low.
1 Arduino MEGA 2560 board, 2 HC-SRO4 ultrasonic sensors, 1 LCD display, 1 Potentiometer, 1 Membrane Keypad, 1 Active Buzzer, 1 Breadboard, 2 LEDs (green and red), 2 220Ω resistors, Several jumper-wires
Working Voltage: DC 5V, Working Current: 15mA, Working Frequency: 40Hz, Min Range: 2cm, Max Range: 4m, Measuring Angle: 15°.
Pin-out
VCC: Power GND: Ground TRIG: trigger output ECHO: echo input
Rated Voltage: 5V DC, Operating Voltage: 4~8V, Max Rated Current: ≤32 mA, Min. Sound Output: at 10cm 85 dB, Resonant Frequency: 2300 ±300 Hz, Operating Temperature: -20°C to 45°C
Pin-out
Longer pin is the positive pin, GND
Number of Keys: 16, Layout: 4x4, Current Rating: 30 mA, Voltage Rating: 12V DC Lifetime: 1 million clicks or more, Reclosing time: ≤5ms
Pin-out
8-pin access to the matrix
Operating voltage: 5±0.3V DC, Operating current: 1mA (without backlight), Controller: Hitachi HD44780 LCD controller, Screen resolution: 2 lines x 16 characters, Character resolution: 5 x 8 pixels
Pin-out
| Pin no. | Label | Connection | Function |
|---|---|---|---|
| 1 | VSS | GND | Signal ground |
| 2 | VDD | 5V | Logic power for LCD |
| 3 | V0 | 10 kΩ potentiometer | Contrast adjustment |
| 4 | RS | Pin 7 | Register select signal |
| 5 | R/W | GND | Read/write select signal (grounded to write) |
| 6 | E | Pin 8 | Operation enable signal |
| 7–14 | D0 – D7 | Data bus lines used for 8-bit mode | |
| 11-14 | D4 – D7 | Pin 9-12 | Data bus lines used for 4-bit mode |
| 15 | A (LED+) | 5V | Anode for LCD backlight |
| 16 | K (LED-) | GND | Cathode for LCD backlight |
