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setup()

Run code once at beginning of program
loop() Loop code continuously #define constantName value Replace all references to constantName with value at compile time

#include library

Include library in sketch and access its functions == Control Structures == if (expression A) {do thing A} Do thing A if expression A is true

else if (expression B) {do thing B}

Do thing B if expression A is false and expression B is true else {do thing C} Do thing C if all the above „if“ and „else if“ blocks are false for(int x = 0; x < 100; x++){println(x)}

Set x to 0, then while x is less than 100, print X and increment x by 1

while(statement){expression}

Keep doing expression while statement is true

do{statement}while(expression);

Like while loop, except expression is evaluated after statement runs once

switch (var) {case 1: statement A break; case 2: statement B break; default: statement C break}

Run statement A, B or C depending on whether var is 1, 2 or a different value

break;

Exit a for, while, do while loop or switch statement

continue;

Skip rest of current iteration of for, while, or do while loop, start next iteration

return value;

Terminate the function and optionally return value to the function that called it

goto label;

Send the program flow to `label:`

Comparison Operators ==

Equals

!=

Is not equal to

<

Less than

>

Greater than

⇐

Less than or equal to

>=

Greater than or equal to

Boolean Operators &&

And

||

Or

!

Not

Bitwise Operators &

And

|

Or

^

Xor

~

Not

«

Bitshift left

»

Bitshift right

Compound Operators x ++

x = x + 1

x –

x = x - 1

x += y

x = x + y

x -= y

x = x - y

x *= y

x = x * y

x /= y

x = x / y

x %= y

x = the remainder of x / y

x &= y

x = x & y

x |= y

x = x | y

Constants HIGH / LOW

Pin input or output voltage is high or low

true / false

Boolean values

INPUT / INPUT_PULLUP / OUTPUT

Configure pin to sample voltage or provide current to other circuits

LED_BUILTIN

Pin where built-in LED is connected

I/O pinMode(pin, mode)

Set pin to either INPUT, OUTPUT, or INPUT_PULLUP

digitalWrite(pin, value)

Set pin to either HIGH or LOW

digitalRead(pin)

Read value of pin, which will be HIGH or LOW

analogReference(type)

Configure refence voltage used for analog input

analogRead(pin)

Return input voltage of pin as integer between 0 and 1023

analogWrite(pin, value)

Output PWM wave to pin with duty cycle of value (between 0 and 255)

Math min(x, y)

Return the smaller of x or y

max(x, y)

Return the greater of x or y

abs(x)

Absolute value of x

constrain(x, a, b)

Limit x to the range a-b, return a or b if x is too small or too large

map(value, fromLow, fromHigh, toLow, toHigh)

Map value from one range of numbers to another

pow(a, x)

Calculate a to the power of x

sqrt(x)

Square root of x

sin(x) / cos(x) / tan(x)

Sine, cosine and tangent of x

randomSeed(x)

Start the pseudo-random number generator at point x

random(min, max)

Generate a pseudo-random number between min (inclusive) and max (exclusive)

Time millis()

Return milliseconds since program started

micros()

Return microseconds since program started

delay(n)

Pause program for n milliseconds

delayMicroseconds(n)

Pause program for n microseconds

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