Mikroelektronika MIKROE-724 データシート

mikroBasic PRO for dsPIC30/33 and PIC24

MikroElektronika

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mikroBasic PRO for dsPIC30/33 and PIC24 uses internal algorithm to distribute objects within memory. If you need to 

have a variable or routine at the specific predefined address, use the linker directives 

absolute

 and 

org

.

Directive absolute

Directive 

absolute

 specifies the starting address in RAM for a variable. If the variable is multi-byte, higher bytes will 

be stored at the consecutive locations.

Directive 

absolute

 is appended to declaration of a variable:

dim x as word absolute 0x32

dim y as longint absolute 0x34

Be careful when using 

absolute

 directive, as you may overlap two variables by accident. For example:

dim  i as word absolute 0x42

dim jj as longint absolute 0x40

Directive orgall

Directive 

org

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

routine declaration.

To place a constant array in Flash memory, write the following:

const MONTHS as byte[12] = (31,28,31,30,31,30,31,31,30,31,30,31) org 0x800

If you want to place simple type constant into Flash memory, instead of following declaration:

const SimpleConstant as byte = 0xAA org 0x2000

use an array consisting of single element:

const SimpleConstant as byte[1] = (0xAA) org 0x800

In first case, compiler will recognize your attempt, but in order to save Flash space, and boost performance, it will 

automatically replace all instances of this constant in code with it’s literal value. 

In the second case your constant will be placed in Flash in the exact location specified.

To place a routine on a specific address in Flash memory you should write the following: