jump.s

ARM嵌入式系统开发--软件设计与优化随书源代码。开发环境asm+c

;  ____________________________________________________________________
; 
;  Copyright (c) 2002, Andrew N. Sloss, Chris Wright and Dominic Symes
;  All rights reserved.
;  ____________________________________________________________________
; 
;  NON-COMMERCIAL USE License
;  
;  Redistribution and use in source and binary forms, with or without 
;  modification, are permitted provided that the following conditions 
;  are met: 
;  
;  1. For NON-COMMERCIAL USE only.
; 
;  2. Redistributions of source code must retain the above copyright 
;     notice, this list of conditions and the following disclaimer. 
; 
;  3. Redistributions in binary form must reproduce the above 
;     copyright notice, this list of conditions and the following 
;     disclaimer in the documentation and/or other materials provided 
;     with the distribution. 
; 
;  4. All advertising materials mentioning features or use of this 
;     software must display the following acknowledgement:
; 
;     This product includes software developed by Andrew N. Sloss,
;     Chris Wright and Dominic Symes. 
; 
;   THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND ANY 
;   EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
;   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
;   PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE 
;   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 
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;  If you have questions about this license or would like a different
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; 	[e-mail]
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; 
; *****************************************************************************
; * Simple Little Operating System - mpuSLOS
; *****************************************************************************

; *****************************************************************************
; * 
; * Module      : jump.s
; * Description : jumps into the first task
; * OS          : mpuSLOS 0.03
; * History     :
; *
; * 14th July 2002 Andrew N. Sloss
; * - added a new jump mechanism
; *
; *****************************************************************************

     EXPORT     jumpToTask1

     AREA jump,CODE,READONLY

; -- JumpToTask1 --------------------------------------------------------------
;
; Description : sets the SPSR to User Mode and enables IRQ's 
; Parameters  : r0 - address on task1
; Return      : never
; Notes       : this routine is required for MPU version of the
;               code.
;

jumpToTask1
        
     MSR 	   SPSR_c,#0x50
     MOVS    pc,r0
     END