Motorola HC12 Manual De Usuario

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Operating Procedures
Working with Relocatable Sections
MCUez HC12 Assembler
User’s Manual
MOTOROLA
Operating Procedures
221
11.3  Working with Relocatable Sections
A relocatable section is a section whereby the start address is determined at link
time. See modules fibo.asm and fibo.prm in the demo directory.
11.3.1  Defining Relocatable Sections in the Assembly Source File
A relocatable section is defined using the directive
SECTION
.
Example:
Defining a relocatable section containing data:
constSec: SECTION ; Relocatable constant data section.
cst1: DC.B    $A6
cst2: DC.B    $BC
dataSec:  SECTION ; Relocatable data section.
var:  DS.B    1
In the previous portion of code, the label
cst1
will be located at offset 0 from
the section
constSec
start address, and label
cst2
will be located at offset 1
from the section
constSec
 start address.
    1    1                      constSec: SECTION
    2    2   000000 A6          cst1: DC.B    $A6
    3    3   000001 BC          cst2: DC.B    $BC
    4    4
    5    5                      dataSec:  SECTION
    6    6   000000             var:  DS.B    1
Defining a relocatable section containing code:
codeSec:  SECTION
; Relocatable code section.
entry:
   LDAA cst1
; Load value in cst1
   ADDA cst2
; Add value in cst2
   STAA var
; Store in var
   BRA entry