using a for loop to print 20 times '*'

hu_ittcalls.asm

mov ah, 0x0e
call starline
call newline
mov al,'H'
int 0x10
mov al,'u'
int 0x10
call newline
mov al,'*'
call doit20
infloop:
jmp $
newline:
        mov al,0x0a
        int 0x10
        mov al,0x0d
        int 0x10
        ret ; returns to where the call was called ( ? det sentence)
starline:
        mov al,'*'
        call doit20
        ret
doit20:
        mov bx,0
loop:
        cmp bx,20;//itterate it 20 times
        je gohome
        int 0x10
        add bx,1
        jmp loop
gohome:
        ret
times 510-($-$$) db 0
dw 0xaa55

hu_ittcalls.hex

 b4 0e e8 1e 00 e8 12 00 b0 48 cd 10 b0 75 cd 10
 e8 07 00 b0 2a e8 11 00 eb fe b0 0a cd 10 b0 0d
 cd 10 c3 b0 2a e8 01 00 c3 bb 00 00 83 fb 14 74
 07 cd 10 83 c3 01 eb f4 c3 00 00 00 00 00 00 00
 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
 00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa

hu_ittcalls.qemu

Booting from Hard Disk...
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Hu
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