81 lines
1.9 KiB
ArmAsm
81 lines
1.9 KiB
ArmAsm
/*
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* FreeModbus Libary: MCF5235 Demo Application
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* Copyright (C) 2006 Christian Walter <wolti@sil.at>
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* Parts of crt0.S Copyright (c) 1995, 1996, 1998 Cygnus Support
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*
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* File: $Id: crt0.S,v 1.1 2006/05/14 21:59:16 wolti Exp $
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*/
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.title "crt0.S"
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.extern main
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.extern __stack
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.extern __bss_start
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.extern __text_start
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.extern init_main
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.global start
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start:
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/* disable all interrupts on startup. */
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move.w #0x2700, sr
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/* prepare internal SRAM. */
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move.l #__text_start, %d0
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addq.l #1, %d0
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movec %d0, %rambar
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/* prepare stack and frame pointer. */
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move.l #__stack, sp
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link a6, #-8
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/* initialize hardware. */
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jsr init_main
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/* zero out the bss section. */
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move.l #__bss_start, d1
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move.l #_end, d0
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cmp.l d0, d1
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jbeq 3f
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move.l d1, a0
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sub.l d1, d0
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subq.l #1, d0
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2:
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clr.b (a0)+
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subq.l #1, d0
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jbpl 2b
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3:
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/* C library */
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move.l #__FINI_SECTION__, -(%sp)
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jsr atexit
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jsr __INIT_SECTION__
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/* enable interrupts. */
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move.w #0x2000, sr
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/* call main(int argc, char *argv[] */
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move.l #0, -(sp)
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move.l #0, -(sp)
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move.l #0, -(sp)
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jsr main
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lea (sp, 12), %sp
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/* stop on exit from main. */
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1:
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halt
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