Arduino Tutorials and More

5V Linear voltage Regulator 1A Parts List : 1) LM7805 2) 100 nF (ceramic capasitor) 3) 10 uF (electrolite capasitor) 4)100  uF (electrolite capasitor) 5)Breadboard (optional) 6)Vero Board 7) Solder Iron 8) Solder Paste etc.. https://www.instructables.com/id/DIY-5V-Linear-Regulator/ Now put your LM7805 on your breadboard pin 1 is input voltage pin 2 ground pin 3 is output voltage positive part of the 10uF capasitor should be connected with pin3 and a 100nF capasitor will connected with this in parallel. Then the positive part of the 100uF capasitor should be connected with pin1. The circuit is done.

                              4x4 Keypad Pinout/Diagram Arduino to Keypad Connection Diagram After connecting as shown here we need to upload a code on our arduino. Here's the  Code : #include <Keypad.h> const byte numRows= 4; //number of rows on the keypad const byte numCols= 4; //number of columns on the keypad char keymap[numRows][numCols]= { {'1', '2', '3', 'A'}, {'4', '5', '6', 'B'}, {'7', '8', '9', 'C'}, {'*', '0', '#', 'D'} }; byte rowPins[numRows] = {9,8,7,6}; //Rows 0 to 3 byte colPins[numCols]= {5,4,3,2}; //Columns 0 to 3 //initializes an instance of the Keypad class Keypad myKeypad= Keypad(makeKeymap(keymap), rowPins, colPins, numRows, numCols); void setup() { Serial.begin(9600); } //If key is pressed, this key is stored in 'keypressed' variable /...