text: #ifndef __KINEMATICS_H__
  #define __KINEMATICS_H__
  
  // arm lengths
  // arm from shoulder to elbow
  #define L1_MM 100.0
  // forearm from elbow to wrist
  #define L2_MM 75.0
  
  int kinematicsForward(float *x, float *y, float L1, float L2, float S, float E);
  int kinematicsInverse(float x, float y, float L1, float L2, float *S, float *E);
  int kinematicsInverseSmallestDelta(float x, float y, float L1, float L2, float *S, float *E, float currentS, float currentE);
  
  float kinematicsStepToRad(int steps);
  int kinematicsRadToStep(float rad);
  float kinematicsRadToDeg(float rad);
  float kinematicsDegToRad(float deg);
  
  #endif /* __KINEMATICS_H__ */
  