Atmel ARM-Based Evaluation Kit for SAM4S16C, 32-Bit ARM® Cortex® Microcontroller ATSAM4S-WPIR-RD ATSAM4S-WPIR-RD Data Sheet

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SAM4S Series [DATASHEET]

Atmel-11100G-ATARM-SAM4S-Datasheet_27-May-14

Push registers onto, and pop registers off a full-descending stack.
Syntax

PUSH{cond} reglist

POP{cond} reglist

where:
condis an optional condition code, see 

.

reglistis a non-empty list of registers, enclosed in braces. It can contain register

ranges. It must be comma separated if it contains more than one register or 

register range.
PUSH and POP are synonyms for STMDB and LDM (or LDMIA) with the memory addresses for the access based 

on SP, and with the final address for the access written back to the SP. PUSH and POP are the preferred 

mnemonics in these cases.
Operation
PUSH stores registers on the stack in order of decreasing the register numbers, with the highest numbered 

register using the highest memory address and the lowest numbered register using the lowest memory address.
POP loads registers from the stack in order of increasing register numbers, with the lowest numbered register 

using the lowest memory address and the highest numbered register using the highest memory address. 
See 

 for more information.

Restrictions
In these instructions:



 must not contain SP



For the PUSH instruction, reglist must not contain PC



For the POP instruction, reglist must not contain PC if it contains LR.

When PC is in reglist in a POP instruction:



Bit[0] of the value loaded to the PC must be 1 for correct execution, and a branch occurs to this halfword-

aligned address



If the instruction is conditional, it must be the last instruction in the IT block.

Condition Flags
These instructions do not change the flags.
Examples

PUSH

{R0,R4-R7}

PUSH

{R2,LR}

POP

{R0,R10,PC}