;**********************************************************************
;	Program for transmitter
;	Written by: Muhammad Kamran.
;	Department of Electronics, University of Peshawar.
;---------------------------------------------------------------------
;---------------------------------------------------------------------
;	Device1		Device2		Device3		Device4
;	switch1		switch2		switch3		switch4
;
;**********************************************************************

		org 00h
		acall initserial
   switch1:	jb p3.2,switch2
		mov a,#40h
		acall transmit
   switch2:	jb p3.3,switch3
   		mov a,#50h
		acall transmit
    switch3:	jb p3.4,switch4
    		mov a,#60h
		acall transmit
    switch4:	jb p3.5,switch1
   		mov a,#70h
		acall transmit
		ajmp switch1
;----------------------------------------------------------------
;		Transmit Subroutines
;----------------------------------------------------------------
    transmit:	clr ti
		mov sbuf,a
    again:	jnb ti,again
		acall delay
		acall delay
		acall delay
		acall delay
		ret
;-----------------------------------------------------------------------
;		Delay Subroutine
;-----------------------------------------------------------------------
      delay:	mov r0,#00ffh
      delay1:	mov r1,#00ffh
      repeat:	djnz r1,repeat
      		djnz r0,delay1
		ret
;------------------------------------------------------------------------
;		Serial Port Subroutine
;------------------------------------------------------------------------
  initserial:	mov scon,#50h
                mov TMOD,#20h
                mov TH1,#-96
                setb  tr1
		ret
;------------------------------------------------------------------------
		end