ARM VERSION 1.2 manual Is either LDM or STM, Is any one of the following, Full descending stack

ARM Instruction Reference

4.2.4LDM and STM

Load and store multiple registers. Any combination of registers r0 to r15 can be transferred.

Syntax

op{cond}mode Rn{!}, reglist{^} where:

op	is either LDM or STM.
cond	is an optional condition code (see Conditional execution on page 4-4).
mode	is any one of the following:
	IA	increment address after each transfer
	IB	increment address before each transfer
	DA	decrement address after each transfer
	DB	decrement address before each transfer
	FD	full descending stack
	ED	empty descending stack
	FA	full ascending stack
	EA	empty ascending stack.
Rn	is the base register, the ARM register containing the initial address for the
	transfer. Rn must not be r15.

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

Rn.

reglist is a list of registers to be loaded or stored, enclosed in braces. It can contain register ranges. It must be comma separated if it contains more than one register or register range (see Examples on page 4-19).

^is an optional suffix. You must not use it in User mode or System mode. It has two purposes:

•If op is LDM and reglist contains the pc (r15), in addition to the normal multiple register transfer, the SPSR is copied into the CPSR. This is for returning from exception handlers. Use this only from exception modes.

•Otherwise, data is transferred into or out of the User mode registers instead of the current mode registers.

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