nes-proj/platform/pc-6001/ctk/libconio_arch-small.cS

103 lines
1.7 KiB
Plaintext
Raw Normal View History

;;;
;;;
;;; libconio_arch-small.hS
;;;
;;; Architecture depend libconio implementation.
;;; This assembler source contributes basically saving for speed and memory.
;;;
;;; @author Takahide Matsutsuka <markn@markn.org>
;;;
;;; $Id: libconio_arch-small.cS,v 1.1 2007/09/30 12:46:34 matsutsuka Exp $
;;;
;; uses preprocessor to enable definitions
#include "ctk_arch-def.h"
;; export symbols
.globl _clrscr_arch
.globl _libputc_arch
.area _DATA
_screen_offset::
.ds 2
.area _CODE
_libconio_arch_small_start::
_clrscr_arch:
ld hl, #0
ld (#_screen_offset), hl
ld hl, #VRAM_CHAR
ld bc, #VRAM_CHAR + #SCREEN_HEIGHT * #SCREEN_WIDTH
_clrscr_arch_loop1:
ld (hl), #CH_SPACE
inc hl
ld a, h
cp b
jr nz, _clrscr_arch_loop1
ld a, l
cp c
jr nz, _clrscr_arch_loop1
ld hl, #VRAM_ATTR
ld bc, #VRAM_ATTR + #SCREEN_HEIGHT * #SCREEN_WIDTH
_clrscr_arch_loop2:
ld (hl), #COLOR_NORMAL
inc hl
ld a, h
cp b
jr nz, _clrscr_arch_loop2
ld a, l
cp c
jr nz, _clrscr_arch_loop2
ret
_libputc_arch:
ld hl, #2
add hl, sp
ld a, (hl)
_libputc_asm::
push af
ld hl, (#_screen_offset)
ld bc, #SCREEN_HEIGHT * #SCREEN_WIDTH
ld a, b
cp h
jr nz, _libputc_arch_putc
ld a, c
cp l
jr z, _libputc_arch_scroll
_libputc_arch_putc:
ld bc, #VRAM_CHAR
add hl, bc
pop af
ld (hl), a
ld hl, #_screen_offset
inc (hl)
ret nz
inc hl
inc (hl)
ret
_libputc_arch_scroll:
push de
ld hl, #VRAM_CHAR + #SCREEN_WIDTH
ld de, #VRAM_CHAR
ld bc, #SCREEN_HEIGHT * #SCREEN_WIDTH - #SCREEN_WIDTH
push bc
push de
ldir
pop de
pop hl
push hl
ld (#_screen_offset), hl
ld b, #SCREEN_WIDTH
add hl, de
_libputc_arch_scroll_loop:
ld (hl), #CH_SPACE
inc hl
djnz _libputc_arch_scroll_loop
pop hl
pop de
jr _libputc_arch_putc
_libconio_arch_small_end::