Motorola HC12 User Manual

Page 219

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Operating Procedures

Introduction

MCUez HC12 Assembler

User’s Manual

MOTOROLA

Operating Procedures

219

In the previous code, the instruction

LDAA

will be located at address

$C00

and

instruction

ADDA

at address

$C03

, as shown in this code listing.

6

6 ORG $C00

7

7 entry:

8

8

a000C00 B6 0A00

LDAA cst1

; Load value in cst1

9

9

a000C03 BB 0A01

ADDA cst2

; Add value in cst2

10

10 a000C06 7A 0800

STAA var

; Store in var

11

11 a000C09 20F5

BRA entry

To avoid problems during linking or executing an application, an assembly file
should at least:

Initialize the stack pointer (using the instruction LDS).

Publish the application entry point using

XDEF

.

The programmer should ensure that the addresses specified in the source
file are valid addresses for the MCU being used.

11.2.3 Linking an Application Containing Absolute Sections

Applications containing only absolute sections must be linked.

A linker parameter file must contain at least:

Name of the absolute file

Name of the object file which should be linked

Specification of a memory area where the sections containing variables
must be allocated. For applications containing only absolute sections,
nothing will be allocated there.

Specification of a memory area where the sections containing code or
constants must be allocated. For applications containing only absolute
sections, nothing will be allocated.

Specification of the application entry point

Definition of the reset vector

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