stepper.h

#include <Wire.h>
#include <Adafruit_MotorShield.h>

Adafruit_MotorShield AFMS = Adafruit_MotorShield(); 
Adafruit_StepperMotor *stepper[2];

const float stepsInch = 66.676;           // measured
//float stepsInch = 132.38;

const int horizMinimum = stepsInch * 6.0;
const int horizMaximum = stepsInch * 44.0;

//const int rotateMaximum = 200 * 27;         // 200 steps per revolution, 27:1 worm gear
const int rotateMaximum = 200 * 25;         // 200 steps per revolution, 25:1 flat gear

const float stepsDegree = rotateMaximum / 360.0 ;

int horizStep = 0;
int horizMove = 0;
int rotateStep = -1;
int rotateMove = -1;

const int stepperHoriz = 1;
const int stepperRotate = 0;

//--------------------------------------------
void stepperMove(int stepperNumber, int Steps, int Type=DOUBLE) {
  // MICROSTEP doesn't jolt the shuttle as much as DOUBLE
  // SINGLE sometimes has a stutter at start,drops some steps?
  stepper[stepperNumber]->step(abs(Steps), Steps > 0 ? FORWARD : BACKWARD, Type);
  //stepper[stepperNumber]->onestep(Steps > 0 ? FORWARD : BACKWARD, Type);
}
  
//--------------------------------------------
void stepperRelease() {
  stepper[stepperHoriz]->release();
  stepper[stepperRotate]->release();  
}

//--------------------------------------------
void stepperSetup() {
  
  AFMS.begin();  // create with the default frequency 1.6KHz
  //AFMS.begin(1000);  // OR with a different frequency, say 1KHz
  
  //TWBR = ((F_CPU /400000l) - 16) / 2; // Change the i2c clock to 400KHz

  // stepper[0] is the one by the power connection (M1/M2)
  
  stepper[stepperRotate] = AFMS.getStepper(200, 1);
  stepper[stepperRotate]->setSpeed(50);
  stepper[stepperHoriz] = AFMS.getStepper(200, 2);
  stepper[stepperHoriz]->setSpeed(50);
  
  
}