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Motorola HC12 User Manual

Page 133

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Assembler Syntax

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MCUez HC12 Assembler

User’s Manual

MOTOROLA

Assembler Syntax

133

Long branch instructions (LBRA, LBEQ, etc.) expect a signed offset encoded
on two bytes. The valid range for a long branch offset is [–32,768...32,767].

Using the special symbol for location counter, it is possible also to specify an
offset to the location pointer as the target for a branch instruction. The *
(asterisk) refers to the beginning of the instruction where it is specified.

Example:

main:

NOP

NOP

BRA *-2

In this example, after the two

NOP

s have been executed, the application

branches at offset –2 from the BRA instruction (for instance, on label

main

).

Inside an absolute section, expressions specified in a PC relative addressing
mode may be:

A label defined in any absolute section

A label defined in any relocatable section

An external label, defined in an XREF directive

An absolute EQU or SET label

Inside a relocatable section, expressions specified in a PC relative addressing
mode may be:

A label defined in any absolute section

A label defined in any relocatable section

An external label, defined in an XREF directive