2.10.10. Software interrupt instruction

You can use the software interrupt (SWI) instruction to enter Supervisor mode, usually to request a particular supervisor function. The SWI handler reads the opcode to extract the SWI function number. A SWI handler returns by executing the following instruction, irrespective of the processor operating state:

MOVS PC, R14_svc

This action restores the PC and CPSR, and returns to the instruction following the SWI.

IRQs are disabled when a software interrupt occurs.

Copyright © 2005, 2006, 2008. All rights reserved.ARM DDI 0360F