Mikroelektronika MIKROE-350 データシート

Constant is a data whose value cannot be changed during the runtime. Using a con-
stant in a program consumes no RAM memory. Constants can be used in any
expression, but cannot be assigned a new value.

Constants are declared in the declaration part of the program or routine, with the fol-
lowing syntax:

const constant_name [as type] = value

Every constant is declared under unique 

constant_name

which must be a valid

identifier. It is a tradition to write constant names in uppercase. Constant requires
you to specify 

value

, which is a literal appropriate for the given type. 

type

is option-

al and in the absence of it , the compiler assumes the “smallest” type that can
accommodate value.

Note: You cannot omit type if declaring a constant array.

Here are a few examples:

const MAX as longint = 10000
const MIN = 1000      ' compiler will assume word type
const SWITCH = "n"    ' compiler will assume char type
const MSG = "Hello"   ' compiler will assume string type
const MONTHS as byte[12] = (31,28,31,30,31,30,31,31,30,31,30,31)

128

- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 5