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|
;--------------------------------------------------------------------------
; crt0.s - Generic crt0.s for a Z80
;
; Copyright (C) 2000, Michael Hope
;
; This library is free software; you can redistribute it and/or modify it
; under the terms of the GNU General Public License as published by the
; Free Software Foundation; either version 2, or (at your option) any
; later version.
;
; This library 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. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this library; see the file COPYING. If not, write to the
; Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
; MA 02110-1301, USA.
;
; As a special exception, if you link this library with other files,
; some of which are compiled with SDCC, to produce an executable,
; this library does not by itself cause the resulting executable to
; be covered by the GNU General Public License. This exception does
; not however invalidate any other reasons why the executable file
; might be covered by the GNU General Public License.
;--------------------------------------------------------------------------
.module crt0
.globl _main
.area _HEADER (ABS)
;; Reset vector
.org 0
jp init
.org 0x08
reti
.org 0x10
reti
.org 0x18
reti
.org 0x20
reti
.org 0x28
reti
.org 0x30
reti
.org 0x38
reti
.org 0x100
init:
;; Set stack pointer directly above top of memory.
ld sp,#0xFFFF
;; Initialise global variables
call gsinit
call _main
jp _exit
;; Ordering of segments for the linker.
.area _HOME
.area _CODE
.area _INITIALIZER
.area _GSINIT
.area _GSFINAL
.area _DATA
.area _INITIALIZED
.area _BSEG
.area _BSS
.area _HEAP
.area _CODE
__clock::
ld a,#2
rst 0x08
ret
_exit::
;; Exit - special code to the emulator
ld a,#0
rst 0x08
1$:
halt
jr 1$
.area _GSINIT
gsinit::
; ld bc, #l__INITIALIZER
ld a, b
or a, c
jr Z, gsinit_next
; ld de, #s__INITIALIZED
; ld hl, #s__INITIALIZER
ldir
gsinit_next:
.area _GSFINAL
ret
|
