library1.asm

display_letter:
    push ax
    push bx
    mov ah,0x0e             ; Load AH with code for terminal output
    mov bx,0x000f           ; Load BH page zero and BL color (graphic mode)
    int 0x10                ; Call the BIOS for displaying one letter
    pop bx
    pop ax
    ret

display_number:
    mov dx,0
    mov cx,10
    div cx
    push dx
    cmp ax,0
    je display_number_1
    call display_number
display_number_1:
    pop ax
    add al,'0'
    call display_letter
    ret

read_keyboard:
    push ax
    mov ah,0x00             ; Load AH with code for keyboard read
    int 0x16                ; Call the BIOS for reading keyboard
    pop ax
    ret

newline:
    push ax
    mov al,13
    call display_letter
    mov al,10
    call display_letter
    pop ax
    ret

print_string:
    push ax
    push bx
print_string_loop:
    mov al,[bx]
    test al,al
    je end
	push bx
    mov ah,0x0e             ; Load AH with code for terminal output
    mov bx,0x000f           ; Load BH page zero and BL color (graphic mode)
    int 0x10                ; Call the BIOS for displaying one letter
    pop bx
	inc bx
	jmp print_string_loop
end:
    pop bx
    pop ax
    ret

clear_text_screen:
    ; clear screen
    push ax
    mov ah, 0x00
    mov al, 0x03  ; text mode 80x25 16 colours
    int 0x10
    pop ax
    ret