6 ldc2, stc2 – ARM VERSION 1.2 User Manual

Page 179

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ARM Instruction Reference

ARM DUI 0068B

Copyright © 2000, 2001 ARM Limited. All rights reserved.

4-69

4.7.6

LDC2, STC2

Transfer data between memory and coprocessor, alternative instructions.

Syntax

These instructions have three possible forms:

zero offset

pre-indexed offset

post-indexed offset.

The syntax of the three forms, in the same order, are:

op coproc, CRd, [Rn]

op coproc, CRd, [Rn, #{-}offset]{!}

op coproc, CRd, [Rn], #{-}offset

where:

op

is either

LDC2

or

STC2

.

coproc

is the name of the coprocessor the instruction is for. The standard name
is

pn

, where

n

is an integer in the range 0-15.

CRd

is the coprocessor register to load or save.

Rn

is the register on which the memory address is based. If r15 is specified,
the value used is the address of the current instruction plus eight.

-

is an optional minus sign. If

-

is present, the offset is subtracted from

Rn

.

Otherwise, the offset is added to

Rn

.

offset

is an expression evaluating to a multiple of 4, in the range 0-1020.

!

is an optional suffix. If ! is present, the address including the offset is
written back into

Rn

.

Usage

The use of this instruction depends on the coprocessor. See the coprocessor
documentation for details.

Note

LDC2

and

STC2

are always unconditional.

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