/*
 * File : timestwo.c
 * Abstract:
 *       An example C-file S-function for multiplying an input by 2,
 *       y  = 2*u
 *
 * See simulink/src/sfuntmpl_doc.c
 *
 * Copyright 1990-2000 The MathWorks, Inc.
 * $Revision: 1.7 $
 */


#define S_FUNCTION_NAME  timestwo
#define S_FUNCTION_LEVEL 2

#include "simstruc.h"

/*================*
 * Build checking *
 *================*/
#if !defined(MATLAB_MEX_FILE)
/*
 * This file cannot be used directly with the Real-Time Workshop. However,
 * this S-function does work with the Real-Time Workshop via
 * the Target Language Compiler technology. See 
 * matlabroot/toolbox/simulink/blocks/tlc_c/timestwo.tlc   for the C version
 * matlabroot/toolbox/simulink/blocks/tlc_ada/timestwo.tlc for the Ada version
 */
# error This_file_can_be_used_only_during_simulation_inside_Simulink
#endif


/* Function: mdlInitializeSizes ===============================================
 * Abstract:
 *   Setup sizes of the various vectors.
 */
static void mdlInitializeSizes(SimStruct *S)
{
    ssSetNumSFcnParams(S, 0);
    if (ssGetNumSFcnParams(S) != ssGetSFcnParamsCount(S)) {
        return; /* Parameter mismatch will be reported by Simulink */
    }

    if (!ssSetNumInputPorts(S, 1)) return;
    ssSetInputPortWidth(S, 0, DYNAMICALLY_SIZED);
    ssSetInputPortDirectFeedThrough(S, 0, 1);

    if (!ssSetNumOutputPorts(S,1)) return;
    ssSetOutputPortWidth(S, 0, DYNAMICALLY_SIZED);

    ssSetNumSampleTimes(S, 1);

    /* Take care when specifying exception free code - see sfuntmpl_doc.c */
    ssSetOptions(S, SS_OPTION_EXCEPTION_FREE_CODE |
                 SS_OPTION_USE_TLC_WITH_ACCELERATOR);
}


/* Function: mdlInitializeSampleTimes =========================================
 * Abstract:
 *    Specifiy that we inherit our sample time from the driving block.
 */
static void mdlInitializeSampleTimes(SimStruct *S)
{
    ssSetSampleTime(S, 0, INHERITED_SAMPLE_TIME);
    ssSetOffsetTime(S, 0, 0.0);
}


/* Function: mdlOutputs =======================================================
 * Abstract:
 *    y = 2*u
 */
static void mdlOutputs(SimStruct *S, int_T tid)
{
    int_T             i;
    InputRealPtrsType uPtrs = ssGetInputPortRealSignalPtrs(S,0);
    real_T            *y    = ssGetOutputPortRealSignal(S,0);
    int_T             width = ssGetOutputPortWidth(S,0);

    for (i=0; i<width; i++) {
        /*
         * This example does not implement complex signal handling.
         * To find out see an example about how to handle complex signal in 
         * S-function, see sdotproduct.c for details.
         */
        *y++ = 2.0 *(*uPtrs[i]); 
    }
}


/* Function: mdlTerminate =====================================================
 * Abstract:
 *    No termination needed, but we are required to have this routine.
 */
static void mdlTerminate(SimStruct *S)
{
}


#if defined(MATLAB_MEX_FILE)
#define MDL_RTW
/* Function: mdlRTW ===========================================================
 * Abstract:
 *	Since we've declared all are parameters as non-tunable, we need
 *	only provide this routine so that they aren't written to the model.rtw
 *	file. The values of the parameters are implicitly encoded in the
 *	sample times.
 */
static void mdlRTW(SimStruct *S)
{
}
#endif /* MDL_RTW */


#ifdef  MATLAB_MEX_FILE    /* Is this file being compiled as a MEX-file? */
#include "simulink.c"      /* MEX-file interface mechanism */
#else
#include "cg_sfun.h"       /* Code generation registration function */
#endif