symbol relay = b3
symbol stat  = b4

dirs = %11111110

read 1,stat
if stat = 1 then on1
goto off1

begin:
read 2,stat
if stat = 1 then on2
goto off2

loop:
  serin 0,N2400,(254),relay,stat
  if relay = 1 then out1
  goto out2
  goto loop

out1:
  write 1,stat
  if stat = 1 then on1
  goto   off1
goto loop

out2:
  write 2,stat
  if stat = 1 then on2
  goto   off2
goto loop

on1:
  high 1
goto begin

off1:
  low 1
goto begin

on2:
  high 2
goto loop

off2:
  low 2
goto loop