Mikroelektronika MIKROE-350 Fiche De Données

mikroBasic PRO for AVR uses internal algorithm to distribute objects within memo-
ry. If you need to have a variable or routine at the specific predefined address, use
the linker directives 

absolute

and 

org

.

Note: You must specify an even address when using the linker directives.

The directive 

absolute

specifies the starting address in RAM for a variable. If the

variable spans more than 1 word (16-bit), higher words will be stored at the consec-
utive locations.

The 

absolute

directive is appended to the declaration of a variable:

dim x as word absolute 0x32
' Variable x will occupy 1 word (16 bits) at address 0x32

dim y as longint absolute 0x34

' Variable y will occupy 2 words at addresses 0x34 and 0x36

Be careful when using absolute directive, as you may overlap two variables by acci-
dent. For example:

dim  i as word absolute 0x42
' Variable i will occupy 1 word at address 0x42;

dim jj as longint absolute 0x40
' Variable will occupy 2 words at 0x40 and 0x42; thus,

' changing i changes jj at the same time and vice versa

Note: You must specify an even address when using the directive absolute.

The directive 

org

specifies the starting address of a routine in ROM. It is appended

to the declaration of routine. For example:

sub procedure proc(dim par as word) org 0x200
' Procedure will start at the address 0x200;
...

Note: You must specify an even address when using the directive 

org

.

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- SOFTWARE AND HARDWARE SOLUTIONS FOR EMBEDDED WORLD

CHAPTER 3