User manual

ASURO - 57

If we want to place a comment between programming lines, the set of comment words or lines

starts with “/*” and ends with “*/ ”. A single line may also be de ned to be a comment by starting

the line with “//“

. Transforming programming lines into comments is often used to exclude parts

of the program from being processed. The compiler will ignore all comments. Correctly inserted

comments will never cause problems in program execution.

9.1.2. Variables and Datatypes

In programming, variables are being used as container elements for data and they may be

de ned,  lled, read or changed in the course of the program. In order to use a variable, it has

to be declared at  rst. In declarations, variables will be assigned to types and they also may be

provided with an initial value. Types de ne which kind of data are to be stored inside the variable

(integer numbers, positive integers, real numbers, etc....).

Variables are referenced by names, which have to begin with a letter (underscore “_” will be

counted as a letter as well) and may also contain numbers, but none of the other special

characters. Capital letters and noncapital letters will be discerned. As an example: x and X

reference to different variables. Normally capital letters are being used for constants

(which cannot be changed in program  ow, e.g. th number PI = 3.1415) and small letters are being

used for variables.

The following names are reserved words and cannot be used as names for variables:

auto default  oat long sizeof union

break do for register static unsigned

case double goto return struct void

char else if short switch volatile

const enum int signed typedef while

continue extern

The following data types will be used for ASURO programming:

Type Range of values Remarks

char -128 ... +127

a (8 bit long) byte, may store a character

from the alphabet

unsigned char 0 ... 255

unsigned characters, may store positive

values only.

int -32768 .. +32767

two byte values in the range

-32768 .. +32767

unsigned int 0 ... 65535

positive integers in the range 0 ... 65535

 oat

real numbers

According to C++ Standards “//” is a comment mark. In fact the compiler for ASURO is a

C++-Compiler and will understand “//” as a comment mark. “//” as a comment mark may

however cause problems in other compilers.

C for ASURO