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Program  : clear screen Procedure
FileName : clrscr.asm
I/P 	 : Nill
O/P 	 : clears the screen
By       : Murugan AD 
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clrscr proc near
   mov ax,0b800h
   mov es,ax
   mov di,0
   mov al,' '
   mov ah,07d
   loop_clear_12:
        mov word ptr es:[di],ax
        inc di
        inc di
        cmp di,4000
        jle loop_clear_12
        ret
endp

Generete Executable using Tasm / Tlink 

tasm filaneme.asm
tlink /t filename

thanks