org 0000h
	ljmp  initialize
	org 001bh
	ljmp  increment
	org  0013h
	ljmp stopa
	org  0100h
initialize:
	mov  ie,#8ch
	;mov  ip,#0ch
	clr  psw.3
	clr  psw.4
	clr  p2.1
	clr  p2.2
	setb p2.0
notnaw:	jb   p2.0,notnaw
	ljmp adirection
org 0200h
adirection:
	setb p2.1
	mov  tl1,#00h
	mov  th1,#00h
	mov  tmod,#10h
	mov  tcon,#44h
waita:
	jnb  p2.1,tobdirection
	sjmp waita
org 0225h
tobdirection:
	ljmp bdirection
org 0250h
increment:
	jnb  p2.1,decre
	inc  r0
	cjne r0,#0ffh,returna
	ljmp stopa
returna: 
	reti
org 0275h
decre:
	dec  r0
	cjne r0,#000h,returnb
	ljmp stopb
returnb:
	reti
org 0285h
bdirection:
	setb ie.7
	setb tcon.6
	setb p2.2
waitb:	sjmp waitb
org 0300h
stopa:
	clr  ie.7
	clr  tcon.6
	clr  p2.1
	lcall towth
	reti
org 0375h
stopb:	clr  ie.7
	clr  tcon.6
	clr  p2.2
org 0400h
towth:
	mov  a,tl1
	cpl  a
	cjne a,#000h,carry
tlend:	mov  tl1,a
	mov  a,th1
	cpl  a
	cjne a,#00h,carryh
thend:	mov  th1,a
	ret
org 0425h
carry:
	inc  a
	ljmp tlend
org 0440h
carryh:
	inc  a
	ljmp thend
end