data types and conversions: variables in arduino programming (part 2)

This article details the most common data types used in Arduino programming.

Data types:

• Array

• A collection of variables that can be accessed via an index number.

• Below are the various methods of declaring arrays:

Key:

int myInts: declares an array without initializing it.

int myPins: declares an array without specifying size.

int mySensVals: declares an array and specifies size.

• Bool

• Can hold either a true or false value.

• Syntax: bool var = val

• Var refers to a variable.

• Val is the value you assign to that variable.

• Char

• A data type used to store a character value.

• Character literals, or just letters, are enclosed by single quotes, whereas a collection of characters, also known as a string, uses double quotes.

• Examples:

• char myLetter = 'A';

• char myInitials = "AL";

• Byte

• Stores an eight bit integer number, from 0-255.

• Syntax: byte var = val

• 'var' and 'val' have the equivalent meaning as they do with respect to the bool data type.

• Float

• Data type for floating-point numbers, or numbers with decimal points.

• Often used to approximate values as they have greater resolution (precision) than integers.

• Syntax: float var = val

• Example:

• float pi = 3.14

• Warnings:

• Floating-point arithmetic takes longer to compute than it would if integers were used.

• The float data type has 6-7 digits of precision (note: not digits after the decimal point, but total digits).

• Int

• Primary data type for number storage.

• Syntax: int var = val

• Void

• Used only in function declarations (ie void loop, void setup)

• Void Indicates that the following function is not expected to return any information to the function from which it was called.

• For example, although there are actions performed within the void setup and void loop functions, no information is returned to the larger program.

Conversions - converting one data type to another:

• byte(x) converts the value x into a byte data type

• char(x) converts the value x into a char data type

• float(x) converts the value x into a float data type

• int(x) converts the value x into an int data type

• etc

#DataTypes #Float #Int #Char #Byte #Bool #Array #Conversions #Arduino #Puriphico