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This example is for Wiring version 0024+. If you have a previous version, use the examples included with your software. If you see any errors or have comments, please let us know.

Wiring and "C" style code by BARRAGAN
Demonstrates how to mix "C" syntax code within a Wiring program. All C code should be enclosed in an extern "C" { } section

     extern "C" {

      typedef int STEPPER_COORD;

      typedef struct _stepper_xy {
        STEPPER_COORD x;
        STEPPER_COORD y;
      }
      STEPPER_POINT;

      void test(STEPPER_POINT *a){
        a->x = 50;
        a->y = 20;
      }

    }

    STEPPER_POINT myPt;

    void setup(){
      Serial.begin(9600);
      myPt.x = 100;  // access the x and y components of
      myPt.y = 100;  // a variable type STEPPER_POINT
      Serial.print("myPt is: ");
      Serial.print(myPt.x, DEC);
      Serial.print(", ");
      Serial.println(myPt.y, DEC);
      test(&myPt);
      Serial.print("now myPt is: ");
      Serial.print(myPt.x, DEC);
      Serial.print(", ");
      Serial.println(myPt.y, DEC);
    }

    void loop()
    {

    }