Relay have become a common use electronic component which operate as an switching device by simply apply voltage to ON and OFF it. For this project, we will discover a simple relay connected with an LED to show what is the basic function and connection.
Besides on directly connected 7 segment with direct I/O port from microcontroller, we can also use the CD4511 (7 segment encoder) to help on decreasing the microcontroller I/O port and only required to send the binary data.
Nowadays, 7 segment has become the most popular display unit on market because it is cheap, easy to program and small. On market, we can found that there was 2 types of 7 segment which is common anode and common cathode. In this project, we are going to use 7 segment with common cathode and directly interface to microcontroller.
A photoresistor or light dependent resistor (LDR) is a resistance decreases with increasing incident light intensity. It can also be referred to as a photoconductor. In here, we going to do a simple connection of LDR and display the ADC and Voltage value on LCD.