/* RLS device emulation. Generates alarms periodicaly on a specified sector.*/

var r1_chanel;  /*0 - 0-80 m, 1 - 80-160 m, 2 - 160-240 m, 3 - 240-320 m*/
var r1_far_near;/*1 - near target detected, 2 - far target detected*/
var r1_barrier_address;

/* RLS device alarm sector */
set_alarm_sector()
{
 r1_chanel = 0;
 r1_far_near = 1;
}

/* RLS device address */
set_radar_address()
{
 r1_barrier_address = 1;
}

/* this entry point is not used*/
main()
{
}

/* this entry point is called on data receive*/
on_read()
{
 var type;
 set_radar_address();
 while(get_in_que_count()>0)
 {
  type = get_poll_type();
  if(type==1)
  {
   process_type1();
  }
  if(type==2)
  {
   process_type2();
  }
 }
}

process_type1()
{
 putx(0x84);
 return 0;
}

process_type2()
{
 var result;
 var cntr;
 var cntr2;

 set_alarm_sector();

 cntr = get_global(1);
 cntr = cntr + 1;
 if(cntr==16)
 {
  cntr = 0;
 }
 set_global(1,cntr);

 if(cntr/4 == r1_chanel)
 {
  if(cntr%4 == 0)
  {
   if(get_global(2)>1)
   {
    set_global(2,0);
   }
   else
   {
    set_global(2,1+get_global(2));
   }
  }
  if(get_global(2)>0)
  {/*normal*/
   result = 0x80 | shl(cntr/4,5);
  }
  else 
  {/*alarm*/
   result = 0x80 | shl(cntr/4,5) | r1_far_near;
  }
 }
 else 
 {/*normal*/
  result = 0x80 | shl(cntr/4,5);
 }
 putx(result);
 return 0;
}

/*returns 0-error, 1-type1, 2-type2*/
get_poll_type()
{
 var ch;
 var addr;
 var type;
 ch = getx();

 if(ch & 0x80 > 0)
 {
  if(ch & 0x20 > 0)
  {
   putx(0x80 | get_global(0));/* 0x80 | address */
   putx(ch);
  }
  return 0;
 }
 type = ch & 0x03;
 addr = shr(ch,2);
 set_global(0,addr);/* store address */

 if(addr != r1_barrier_address)
 {
  return 0;
 }
 if(type == 0)
 {
  return 1;
 }
 if(type == 0x02)
 {
  return 2;
 }
 return 0;
}