anchor.diff:  
       rule update_debug;
           let dval = diff;
  -        dval = {diff[29:0], framestart_wire, fs2};
  +        dval = {diff[29:0], framestart_reg, fs2};
           if (diff[17] == 1)
               begin
               debugind_value <= diff;
  
positive.code:     endrule
  
      rule sframe_calc;
          delay_limit <= host.syncgen_delay();
          let fd = frame_delay+1;
          let fr = frame_run;
          if (sframe_wire == 1)
  
negative.code:     endrule
  
      rule receive_framestart;
          framestart_delay_reg <= sensor.get_framesync();
  	Vector#(4, Bit#(1)) in = replicate(0);
  	// zero'th element shifted out first
  	in[1] = framestart_delay_reg;
  