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.module crt0
.globl _main
.area _HOME
.area _CODE
.area _INITIALIZER
.area _GSINIT
.area _GSFINAL
.area _DATA
.area _INITIALIZED
.area _BSEG
.area _BSS
.area _HEAP
ENASLT = 0x0024
RSLREG = 0x0138
CLIKSW = 0xf3db
.area _CODE
; ROM header
.str "AB"
.dw _main_init
.db 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
; entry point skipping the init code that is used
; when starting from cassette
jp _cas_main
_main_init::
; init the stack
di
ld sp, #0xf380
ei
; setup memory
; ref: https://www.msx.org/forum/msx-talk/development/memory-pages-again
call RSLREG
rrca
rrca
and #3
ld c, a
add a, #0xc1
ld l, a
ld h, #0xfc
ld a, (hl)
and #0x80
or c
ld c, a
inc l
inc l
inc l
inc l
ld a, (hl)
and #0x0c
or c
ld h, #0x80
call ENASLT
_cas_main::
; disable key click sound
xor a
ld (CLIKSW), a
call gsinit
call _main
halt0:
halt
jr halt0
.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
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