Dear pals,i need 8086 codes. Thanks to the two below replies,i can use the stdcall well.
But is there any error in the codes ?

include '8086.inc'
include 'format/mz.inc'
macro stdcall proc,args&
        iterate arg, args
                indx 1+%%-%
                mov bx,arg
                push bx
        end iterate
        call proc
end macro
entry code:start        ; program entry point
stack 100h      ; stack size
        segment code
start:
        push cs
        pop ds
        call main
        MOV AH,4CH
        INT 21H
main:
        push bp
        mov bp,sp
        sub sp,2
        ;
        mov bx,[-2+bp]
        mov byte[bx],10
        mov byte[bx+1],'1'
        mov byte[bx+2],'2'
        mov byte[bx+3],10
        mov byte[bx+4],'$'
        stdcall ok,9,[-2+bp]
        add sp,4
        ;
        mov sp,bp
        pop bp
        ret
ok:
        push bp
        mov bp,sp
        mov bx,[bp+6]
        mov byte[bx+2],'h'
        mov dx,bx
        mov ah,9
        int 21h
        ;
        mov dx,[bp+4]
        add dx,30h
        mov ah,2
        int 21h
        ;
        mov sp,bp
        pop bp
        ret