boot.asm
1.56 KB
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;BLACK 0x0
;BLUE 0x1
;GREEN 0x2
;CYAN 0x3
;RED 0x4
;MAGENTA 0x5
;BROWN 0x6
;GREY 0x7
;DARK_GREY 0x8
;LIGHT_BLUE 0x9
;LIGHT_GREEN 0xA
;LIGHT_CYAN 0xB
;LIGHT_RED 0xC
;LIGHT_MAGENTA 0xD
;LIGHT_BROWN 0xE
;WHITE 0xF
[BITS 16]
[org 0x7C00]
JMP short Start
str: db 'THE GAME ',0x00
Start:
XOR ax, ax
MOV ds, ax
CALL clear_screen
PUSH 2 ; num
PUSH 2 ; offset
;CALL print_sector ; (offset, num)
;ADD esp, 12
for_start_0:
MOV si,str
CALL print_string
;JMP for_start_0
JMP $
clear_screen:
MOV al, 02h ; Setting the graphical mode 80x25(text)
MOV ah, 00h ; Code of the function of changing video mode
INT 10h ; Call interruption
RETN
print_string: ; Expects null terminated message in si
;MOV bl,0x00
for_print_string_0:
MOV al,[si]
OR al,al
JZ .end
INC si
CALL print_char
;INCL bl
JMP for_print_string_0
.end:
RETN
print_sector:
PUSH ebp
MOV ebp, esp
PUSH ax
PUSH bx
PUSH cx
PUSH dx
MOV al, [12 + ebp]
MOV cl, [8 + ebp]
MOV ah, 2
MOV ch, 0
MOV dh, 0
INT 0x13
POP dx
POP cx
POP bx
POP ax
MOV esp, ebp
POP ebp
RETN
print_char:
PUSH ebp
MOV ebp, esp
PUSH ax
PUSH bx
MOV ah,0x0E ; Specifies that we want to write a character to the screen
MOV bl,0x02 ; Specifies output text color. Not required, but useful to know
MOV bh,0x00 ; Page number. Leave this alone.
INT 0x10 ; Signal video interrupt to BIOS
POP bx
POP ax
MOV esp,ebp
POP ebp
RETN
TIMES 510 - ($ - $$) db 0
DW 0xAA55