How to Wire the GT-511C3 Fingerprint Scanner

The article on the GT-511C3 fingerprint scanner hardware, wiring and connector numbering shows how to connect the fingerprint scanner module to 5V and 3.3V microcontrollers using the Arduino Uno and Arduino Due as examples.

The article includes the pin numbers and functions as well as voltage levels and default baud rate. Information is provided that shows how to make up a cable with connector that will plug into the GT-511C3 FPS (fingerprint scanner).

Go to the article →

Simple Raspberry PI Serial Port and Breakout Board

Add a RS232 serial port and GPIO breakout to your Raspberry PI using this simple single-sided circuit board that you can build at home.

To keep the design simple and easy to lay out on a single sided board, only 5 GPIO pins were connected to a socket strip – this is fine for initial experimentation. The serial port allows the Raspberry PI to be connected to a PC without the need to connect a keyboard and screen to the Raspberry PI.

Go to the article on the Raspberry PI serial port and breakout board to see the circuit diagram and source files in KiCad format.

Arduino Buzzer Connection Circuit

A buzzer can be directly connected to an Arduino if it operates at the same voltage as the Arduino (usually 5V) and does not need to draw more current than an Arduino pin can deliver.

But what if the buzzer operates at a different voltage to the Arduino and / or needs to draw more current than the Arduino pin is capable of supplying? One solution is to use a transistor to interface the buzzer to the Arduino. The Arduino buzzer transistor connection circuit on the Starting Electronics website shows how to connect the buzzer to the Arduino using an NPN transistor.

Note that the piezo buzzer used in the circuit is not a plain piezo element, but sold as a piezo buzzer that has built-in circuitry that makes the buzzing sound when power is applied to it.

Processing Language System Requirements

The Processing language can be used in electronics applications for interfacing microcontroller circuits to a PC. The computer interface software can be written in Processing and allow a user to interact with the microcontroller circuit or embedded system. The Arduino can be interfaced to a computer in this way and there are many Arduino / Processing PC interfacing examples on the Internet (e.g. the Arduino relay shield project).

The article on the system requirements for the Processing language explains the hardware and software requirements for running Processing.