Samsung S3C2440A User Manual

Page 65

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ARM INSTRUCTION SET

S3C2440A RISC MICROPROCESSOR

3-8

ASSEMBLER SYNTAX

Items in “{}” are optional. Items in “<>” must be present.

B{L}{cond} <expression>

{L}

Used to request the Branch with Link form of the instruction.

If absent, R14 will not be affected by the instruction.

{cond}

A two-character mnemonic as shown in Table 3-2.

If absent then AL (ALways) will be used.

<expression>

The destination. The assembler calculates the offset

Examples

here BAL here

; Assembles to 0xEAFFFFFE (note effect of PC offset).

B there

; Always condition used as default.

CMP

R1,#0

; Compare R1 with zero and branch to fred

if R1 was zero, otherwise continue.

BEQ

fred

; Continue to next instruction.

BL

sub+ROM

; Call subroutine at computed address.

ADDS

R1,#1

; Add 1 to register 1, setting CPSR flags

on the result then call subroutine if

BLCC

sub

; the C flag is clear, which will be the

case unless R1 held 0xFFFFFFFF.

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