Using interrupts on the Arduino Nano

[johnerrington]

@ghoshofx1

This task is a precursor to a bigger project. I am building a home security system with a bunch of PIR and ultrasonic sensors. There's a matrix keypad for password entry. There's an alarm (buzzer) that goes off along with a red LED flashing. Green LED shows the system is disarmed. Yellow LED shows the system is armed.

So - apart from having three LEDs - what doees that have to do with traffic lights? Do you have so much traffic at home you need to control the flow?

The TWO DIFFERENT situations you describe are classic examples for the use of a state machine.
My tutorial below has the traffic lights as an example.

Beginners: using the switch - case statement

The switch - case statement is a powerful construct that is often under-used by beginners. Basically it allows you to perform tests on a value (or range of values) and make decisions - a bit like the IF statement. This tutorial has three examples that progressively introduce some simple ideas to help you use the switch construct in your programming. You will need an Arduino Uno (the programs will run on most arduinos) three leds - preferably red, yellow, green - some resistors around 220 ohms…

States Machine Example

Hello! I wanted to write some example for begginers so i decided to make this simple states machine example which only needs Arduino Starter Kit materials . this is the circuit if you need to check connections: States Machine Example /*   States Machine   Sometimes you will need to switch between whats going to be executed on the loop section,   this is called the machine state, it can be multiple things like diferent methods of motor   control, switching between manual or aut…