##==============================================================================
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##==============================================================================
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##
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##
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## crt0.S
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## crt0.S
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##
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##
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## MN10200 startup code
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## MN10200 startup code
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##
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##
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##==============================================================================
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##==============================================================================
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##
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##
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## Copyright (c) 1995, 1996, 1997, 1998 Cygnus Solutions
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## Copyright (c) 1995, 1996, 1997, 1998 Cygnus Solutions
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##
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##
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## The authors hereby grant permission to use, copy, modify, distribute,
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## The authors hereby grant permission to use, copy, modify, distribute,
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## and license this software and its documentation for any purpose, provided
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## and license this software and its documentation for any purpose, provided
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## that existing copyright notices are retained in all copies and that this
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## that existing copyright notices are retained in all copies and that this
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## notice is included verbatim in any distributions. No written agreement,
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## notice is included verbatim in any distributions. No written agreement,
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## license, or royalty fee is required for any of the authorized uses.
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## license, or royalty fee is required for any of the authorized uses.
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## Modifications to this software may be copyrighted by their authors
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## Modifications to this software may be copyrighted by their authors
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## and need not follow the licensing terms described here, provided that
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## and need not follow the licensing terms described here, provided that
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## the new terms are clearly indicated on the first page of each file where
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## the new terms are clearly indicated on the first page of each file where
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## they apply.
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## they apply.
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##
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##
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|
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##------------------------------------------------------------------------------
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##------------------------------------------------------------------------------
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.file "crt0.S"
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.file "crt0.S"
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##------------------------------------------------------------------------------
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##------------------------------------------------------------------------------
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## Startup code
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## Startup code
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.section .text
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.section .text
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.global _start
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.global _start
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_start:
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_start:
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mov _stack,a3 # Load up the stack pointer and allocate
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mov _stack,a3 # Load up the stack pointer and allocate
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# our current frame.
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# our current frame.
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mov _edata,a0 # Get the start/end of bss
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mov _edata,a0 # Get the start/end of bss
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mov _end,a1
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mov _end,a1
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cmp a0,a1 # If no bss, then do nothing
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cmp a0,a1 # If no bss, then do nothing
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beqx .L0
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beqx .L0
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sub d0,d0 # clear d0
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sub d0,d0 # clear d0
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.L1:
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.L1:
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movb d0,(a0) # Clear a byte and bump pointer
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movb d0,(a0) # Clear a byte and bump pointer
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add 1,a0
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add 1,a0
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cmp a0,a1
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cmp a0,a1
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bnex .L1
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bnex .L1
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.L0:
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.L0:
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jsr ___main
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jsr ___main
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sub d0,d0
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sub d0,d0
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mov d0,d1
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mov d0,d1
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mov d0,(a3)
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mov d0,(a3)
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jsr _main # Call main program
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jsr _main # Call main program
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jmp _exit # All done, no need to return or
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jmp _exit # All done, no need to return or
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# deallocate our stack.
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# deallocate our stack.
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.section .stack
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.section .stack
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_stack: .long 1
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_stack: .long 1
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