component variator "LinuxCNC HAL component to scale variator";

pin out bit up_relay = 0        "Turn Up relay on";
pin out bit down_relay = 0      "Turn Down relay on";
pin in  bit home                "Home the Variator";
pin in unsigned vgear = 0       "Virtual gear to select - homed to gear 0';
param float traversetime = 5.0  "time to traverse the full scale";
param float numgears = 6        "number of gears to traverse full scale";

function _;
license "GPL";
;;

enum states{HOMING, RUNNING, CHANGING, UP, DOWN};
enum states state = HOMING;
FUNCTION(_) {
  static int last_vgear;
  static float timecount = 0.0;  // this is the time we have been running
  float timeslice = traversetime / (numgears -1) ;     // time it takes to traverse a single gear

  switch(state){
    case HOMING:
       down_relay = 1;
       if(home){
        down_relay = 0;
        state = RUNNING;
       }
       break;
    case RUNNING:
       if(vgear != last_vgear){
         // the gear has changed
         gearchangetime = abs((vgear - last_vgear)) * traversetime;
         timecount = 0.0;
         if(vgear > last_vgear){
           state = UP;
         }
         else{
           state = DOWN;
         }
       }
       // fall through on this cycle so no break;
    case UP:
       down_relay = 0;
       up_relay = 1;
       state = CHANGING;
       break;
    case DOWN:
       down_relay = 1;
       up_relay = 0;
       state = CHANGING;
       break;
    case CHANGING:
       timecount += fperiod;
       if(timecount > gearchangetime){
         timecount = 0.0;
         down_relay = 0
         up_relay = 0;
         state = RUNNING;
       }
       break;
  }
  last_vgear = vgear;
}