swi.s

来自「现在ST91的ARM使用比较广泛。这里是该芯片的一些驱动。可能会用的上」· S 代码 · 共 31 行

;/*****************************************************************************/
;/* SWI.S: SWI Handler                                                        */
;/*****************************************************************************/
;/* This file is part of the uVision/ARM development tools.                   */
;/* Copyright (c) 2005-2006 Keil Software. All rights reserved.               */
;/* This software may only be used under the terms of a valid, current,       */
;/* end user licence from KEIL for a compatible version of KEIL software      */
;/* development tools. Nothing else gives you the right to use this software. */
;/*****************************************************************************/


        AREA SWI, CODE, READONLY 
        ARM

        PRESERVE8
        ALIGN
        IMPORT  SWI_Handler
        EXPORT  SWIHandler

SWIHandler
        STMFD   SP!, {R0-R12, LR}       ; Save Workspace & LR to Stack
        MRS     R0, SPSR                ; Copy SPSR to R0
        STMFD   SP!, {R0, R1}           ; Save SPSR to Stack (8-byte)
        BL      SWI_Handler             ; Branch to SWI Handler
        LDMFD   SP!, {R0, R1}           ; Restore SPSR to R0
        MSR     SPSR_cxsf, R0           ; Restore SPSR
        LDMFD   SP!, {R0-R12, PC}^      ; Return to program after
                                        ; SWI Instruction

        END