Transcript Arduino_0

ARDUINO CLUB
What we’re really doing
BASICS
The setup() and loop() functions
void setup()
• Like the main() you’re used to
• For setting pin modes
• pinMode(pinNumber,MODE);
• MODE can be ‘INPUT’ or ‘OUTPUT’
• pinNumber is the number of the pin
• Useful to start serial connection here
• Serial.begin(9600);
• Only run once, when the arduino board powers on
void loop()
• Also like main()
• This is where you put your actual program
• This loops until the board loses power, or breaks
CONTROLLING PINS
But I want to make my LED flash! D:
digitalWrite()
• Basically, turns things on and off
• digitalWrite(pinNumber,STATE);
• pinNumber can be any pin that was set, in the the setup, to be an
output
• STATE can either be ‘HIGH’ or ‘LOW’ (on or off)
digitalRead()
• Checks if inputs are high, or low
• digitalRead(pinNumber)
• pinNumber can be any pin that you set as an INPUT in the setup
loop
• Will return either HIGH or LOW
delay()
• Pauses the program for a set amount of time
• delay(time);
• Time is in milliseconds, so 1 second would be delay(1000)
WIRING
Make sure you don’t blow things up
LEDs
• Require 220Ω resistor (red, red, brown)
CONDITIONALS
"If" Statements
These allow us to perform an action, if a condition is met, and
otherwise perform another action
#include<stdio.h>
int i;
void main(){
printf("Enter a number! \n");
scanf("%d",&i);
if (i == 0){
printf("that number was zero \n");
} else {
printf("that number was not zero \n");
}
}
Logic Operators
• == means equal to
• != means not equal to
• && means AND
• || means OR
• > means greater than
• < means less than
• >= means greater than or equal to
• <= means less than or equal to
Buttons
• Need to be connected to ground as well as +volts
LOOPS
"While" Loops
These allow us to loop code indefinitely until a condition is
met:
#include<stdio.h>
//You get the point
int x = 0;
//Declares x variable
void main(){
while(x<100){
x++;
printf("%d \n",x);
}
}
//Starts main
//Starts while loop with condition
//Increases x by one
//Prints value of x
"For" Loops
• Used for performing actions a set amount of times
• Also useful for looping through an ARRAY
• Started by:
"for (initialization, condition, increment) {(functions in here)}"
• Initialization is run only once, and is usually decleration of the condition variable
• Condition decides when the for loop will stop, once it is false the loop will be exited
• The increment decides how the condition variable will be increased/decreased
#include<stdio.h>
void main(){
for (int x = 0; x<100; x++){
printf("%d \n", x);
}
}
/* includes stdio library,
necessary */
// starts main function
// sets how the for loop will run
/* prints "x" until it"s equal to
100, then stops */
"For" Loops with Arrays
We can also iterate through an array with a for loop, as
shown below:
#include<stdio.h>
//Necessary
int myNum[2]={1,3};
//Defines array
int arraySize=sizeof(myNum)/sizeof(int);
//Works out length of the array
int i=0;
//Defines i for iterating
void main(){
//Starts main
for(i=0;i<arraySize;i++){
//Starts for loop
printf("%d \n",myNum[i]); //Outputs each field
}
}
A Note about Iterating
• Iterators usually take the form of:
• Variable++
• This will increase "Variable" by one every iteration
• Variable-• This will decrease "Variable" by one every iteration
• We aren’t limited to this, an iterator can have any
mathematic function applied to it, however these are the
most common