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;; boot.stage2.print.asm
section .stage2
%define VGA_BUFFER 0xb8000
%define WB_COLOR 0xf
_print_string_pm_vga:
mov eax, [esi]
lea esi, [esi+1]
cmp al, 0
jne .print_char_pm_vga
add byte [pos_x], 0
add byte [pos_y], 1
ret
.print_char_pm_vga:
mov ah, WB_COLOR ; White on black
mov ecx, eax
movzx eax, byte [pos_y]
mov edx, 160
mul edx
movzx ebx, byte [pos_x]
shl ebx, 1
mov edi, VGA_BUFFER ; Video memory start
add edi, ebx ; Add X offset
add edi, eax ; Add Y offset
mov eax, ecx ; Restore char
mov word [ds:edi], ax
add byte [pos_x], 1 ; Advance to right
ret
pos_x: db 0
pos_y: db 0
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