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;/****************************************************************

;KPIT Cummins Infosystems Ltd, Pune, India. - 4th September 2003.

;

;This program is distributed in the hope that it will be useful,

;but WITHOUT ANY WARRANTY; without even the implied warranty of

;MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE

;

;*****************************************************************/

;*********************************************************************

; File: start.asm

;

;

; desc:

;

;  System initialisation routine - entry point for the application.

;  The stack pointer is initialised, then the hardware initialisation

;  routine called.  The static data areas are then initialised, before

;  the main function is executed.  A simple exit funtion is also

;  supplied

;

;*********************************************************************

#ifdef __H8300H__

#ifdef __NORMAL_MODE__

        .h8300hn

#else

        .h8300h

#endif

#endif  /*_H8300H_ */

#ifdef __H8300S__

#ifdef __NORMAL_MODE__

        .h8300sn

#else

        .h8300s

#endif

#endif /* __H8300S__ */

        .section .text

        .global _start

#if DEBUG

        .extern _exit

#endif

        .extern _hw_initialise

        .extern _main

        .extern _data

        .extern _mdata

        .extern _edata

        .extern _bss

        .extern _ebss

        .extern _stack

_start:

        ; initialise the SP for non-vectored code

    mov.l   #_stack,er7

        ; call the hardware initialiser

        jsr     @_hw_initialise

#ifdef ROMSTART

        ; get the boundaries for the .data section initialisation

    mov.l   #_data,er0

    mov.l   #_edata,er1

    mov.l   #_mdata,er2

    cmp.l   er0,er1

        beq     start_1

start_l:

    mov.b   @er2,r3l  ;get from src

    mov.b   r3l,@er0  ;place in dest

    inc.l   #1,er2    ;inc src

    inc.l   #1,er0    ;inc dest

    cmp.l   er0,er1   ;dest == edata?

        bne     start_l

start_1:

#endif          //ROMSTART

        ; zero out bss

    mov.l   #_bss,er0

    mov.l   #_ebss,er1

    cmp.l   er0,er1

        beq     start_3

        sub.b   r2l,r2l

start_2:

    mov.b   r2l,@er0

    inc.l   #1,er0

    cmp.l   er0,er1

        bne     start_2

start_3:

#ifdef CPPAPP

        ;Initialize global constructor

        jsr     @___main

#endif

        ; call the mainline

        jsr     @_main

    mov.l   er0,er4

    ;call to exit

#if DEBUG

    jsr     @_exit

#endif

#if RELEASE

 exit:

        bra     exit

#endif