[SuperBK]

Use a counter. Its 26.2 ms for each time User_Autonomous_Code() is called.

#define STAGE_1 0   
#define STAGE_2 1
#define STAGE_3 2

inside User_Autonomous_Code()

static stage;
int counter;

state = STAGE_1;


  while (autonomous_mode)   /* DO NOT CHANGE! */
  {
switch (stage)
{
  case STAGE_1:
   // turn motor on here
   counter =  0;
   stage = STAGE_2;
   break;
   
   case STAGE_2:
   ++counter;
   if (counter = 38)    // 1 second
   {
      // turn motor off here
     stage = STAGE_3
   }
      break;
}
}