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# Copyright (c) KATO Takenori, 1999, 2000.
#
# All rights reserved. Unpublished rights reserved under the copyright
# laws of Japan.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# 1. Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer as
# the first lines of this file unmodified.
# 2. Redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# $FreeBSD$
#
.code16
.text
#
# %al character code
# destroyed: %al, %bx
#
put_character:
movw $0xe000, %bx
movb ishireso, %ah
orb %ah, %ah
jne hireso_ch
movw $0xa000, %bx
hireso_ch:
movw %bx, %es
xorb %ah, %ah
movw curpos, %bx
movw %ax, %es:(%bx)
xorw %ax, %ax
movw %ax, %es
ret
#
# %al attribute
# destroyed: %ah, %cx
#
set_attribute:
movw $0xe200, %bx
movb ishireso, %ah
orb %ah, %ah
jne hireso_ch
movw $0xa200, %bx
hireso_attr:
movw %bx, %es
xorb %ah, %ah
movw curpos, %bx
movw %ax, %es:(%bx)
xorw %bx, %bx
movw %bx, %es
ret
#
# Put a character
# %al: character code
# destroyed: %ah, %bx, %cx
#
.global sc_putc
sc_putc:
call put_character
incw curpos
incw curpos
cmpw $4000, curpos
jng putc_end
movw $0, curpos
putc_end:
ret
#
# Put a null terminated string
# %di: pointer to string
# destroyed: %ah, %cx, %di
#
.global sc_puts
sc_puts:
movb (%di), %al
orb %al, %al
jz puts_end
call sc_putc
incw %di
jmp sc_puts
puts_end:
ret
#
# Change the current cursor position
# %cx: X
# %dx: Y
# destroyed: %ax, %bx
#
.global sc_goto
sc_goto:
movw %dx, %ax # AX=Y
shlw %ax # AX=Y*64
shlw %ax
shlw %ax
shlw %ax
shlw %ax
shlw %ax
movw %dx, %bx # BX=Y
shlw %bx # BX=Y*16
shlw %bx
shlw %bx
shlw %bx
addw %bx, %ax # AX=Y*64+Y*16=Y*80
addw %cx, %ax
shlw %ax
movw %ax, curpos
ret
#
# Clear screen
# destroyed: %ax, %bx
#
.global sc_clean
sc_clean:
movb $0x16, %ah
movw $0xe120, %dx
int $0x18 # KBD/CRT BIOS
movw $0, curpos
ret
#
# Set sttribute code
# %al: attribute
# %cx: count
# destroyed: %ax, %bx, %cx
#
.global sc_setattr
sc_setattr:
call set_attribute
incw curpos
incw curpos
loop sc_setattr
#
# Sense the state of shift key
# destroyed: %ax
#
.global sc_getshiftkey
sc_getshiftkey:
movb $2, %ah # Sense KB_SHIFT_COD
int $0x18 # KBD/CRT BIOS
xorb %ah, %ah
ret
#
# Check KBD buffer
#
.global sc_iskeypress
sc_iskeypress:
mov $1, %ah
int $0x18 # KBD/CRT BIOS
testb $1, %bh
jz no_key
movw $1, %ax
ret
no_key:
xorw %ax, %ax
ret
#
# Read from KBD
#
.global sc_getc
sc_getc:
xorb %ah, %ah
int $0x18
ret
#
# Initialize CRT (normal mode)
#
init_screen_normal:
# Disable graphic screen
movb $0x41, %ah
int $0x18
# Init graphic screen
movb $0x42, %al
movb $0xc0, %ch
int $0x18
# 80x25 mode
movw $0x0a00, %ax
int $0x18
ret
#
# Initialize CRT (hireso mode)
#
init_screen_hireso:
# Init RAM window
movb $8, %al
outb %al, $0x91
movb $0x0a, %al
outb %al, $0x93
# 80x31 mode
movw $0x0a00, %ax
int $0x18
ret
#
# Initialize screen (internal)
#
init_screen:
movb ishireso, %ah
orb %ah, %ah
jne hireso_ini
call init_screen_normal
jmp init_next
hireso_ini:
call init_screen_hireso
init_next:
movb $0x0c, %ah
int $0x18
# cursor home and off
xorw %dx, %dx
movb $0x13, %ah
int $0x18
movb $0x12, %ah
int $0x18
ret
#
# Initialize screeen
#
.global sc_init
sc_init:
call init_screen
call sc_clean
movw $0, curpos
ret
.data
curpos: .word 0 # Current cursor position
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