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SECTION .text
USE16
; provide function for printing in x86 real mode
; a newline
newline: db 0xD, 0xA, 0
; print a string and a newline
; IN
; si: points at zero-terminated String
; CLOBBER
; ax
print_line:
mov si, newline
call print
ret
; print a string
; IN
; si: points at zero-terminated String
; CLOBBER
; ax
print:
lodsb
test al, al
jz .done
call print_char
jmp print
.done:
ret
; print a character
; IN
; al: character to print
; CLOBBER
; ah
print_char:
mov ah, 0x0e
int 0x10
ret
; print a number in hex
; IN
; bx: the number
; CLOBBER
; cx, ax
print_num:
mov cx, 4
.lp:
mov al, bh
shr al, 4
cmp al, 0xA
jb .below_0xA
add al, 'A' - 0xA - '0'
.below_0xA:
add al, '0'
call print_char
shl bx, 4
loop .lp
ret