dcl_df23.h

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#ifndef _DCL_DF23_H_
#define _DCL_DF23_H_
 
#ifdef __cplusplus
extern "C" {
#endif
 
#include "../dcl_common.h"
 
//--- Direct Form 2 - 3rd order ----------------------------------------------
 
typedef struct dcl_df23_sps
{
    float32_t b0;   
    float32_t b1;   
    float32_t b2;   
    float32_t b3;   
    float32_t a1;   
    float32_t a2;   
    float32_t a3;   
} DCL_DF23_SPS;
 
#define DF23_SPS_DEFAULTS { 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f }
 
typedef _DCL_VOLATILE struct dcl_df23
{
    /* compensator parameter */
    float32_t b0;   
    float32_t b1;   
    float32_t b2;   
    float32_t b3;   
    float32_t a1;   
    float32_t a2;   
    float32_t a3;   
 
    /* internal storage */
    float32_t x1;   
    float32_t x2;   
    float32_t x3;   
 
    /* miscellaneous */
    DCL_DF23_SPS *sps; 
    DCL_CSS *css;      
} DCL_DF23;
 
#define DF23_DEFAULTS { 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, \
                        0.0f, 0.0f, 0.0f, 0.0f, 0.0f, \
        &(DCL_DF23_SPS)DF23_SPS_DEFAULTS, &(DCL_CSS)DCL_CSS_DEFAULTS }
 
#define DF23_INT_DEFAULTS .x1=0.0f, .x2=0.0f, .x3=0.0f, \
.sps=&(DCL_DF23_SPS)DF23_SPS_DEFAULTS, .css=&(DCL_CSS)DCL_CSS_DEFAULTS 
 
#define DCL_initDF23() &(DCL_DF23)DF23_DEFAULTS
 
#define DCL_initDF23asParam(_b0,_b1,_b2,_b3,_a1,_a2,_a3) &(DCL_DF23){ .b0=_b0, .b1=_b1, \
                        .b2=_b2, .b3=_b3, .a1=_a1, .a2=_a2, .a3=_a3, DF23_INT_DEFAULTS }
 
#define DCL_initDF23asSPS(df_ptr,sps_ptr)                                          \
({                                                                                 \
    DCL_DF23* new_df = (df_ptr) ? df_ptr : DCL_initDF23();                         \
    DCL_DF23_SPS* new_sps = (sps_ptr) ? sps_ptr : &(DCL_DF23_SPS)DF23_SPS_DEFAULTS;\
    if(sps_ptr)                                                                    \
    {                                                                              \
        *new_df = (DCL_DF23){ (new_sps)->b0, (new_sps)->b1, (new_sps)->b2,         \
        (new_sps)->b3,(new_sps)->a1, (new_sps)->a2, (new_sps)->a3, 0.0f,           \
        0.0f, 0.0f, (DCL_DF23_SPS*)new_sps, &(DCL_CSS)DCL_CSS_DEFAULTS };          \
    }                                                                              \
    new_df;                                                                        \
})
 
_DCL_CODE_ACCESS
void DCL_resetDF23(DCL_DF23 *df)
{
    dcl_interrupt_t ints;
    
    ints = DCL_disableInts();
    df->x1 = df->x2 = df->x3 = 0.0f;
    DCL_restoreInts(ints);
}
 
_DCL_CODE_ACCESS
void DCL_forceUpdateDF23(DCL_DF23 *df)
{
    df->b0 = df->sps->b0;
    df->b1 = df->sps->b1;
    df->b2 = df->sps->b2;
    df->b3 = df->sps->b3;
    df->a1 = df->sps->a1;
    df->a2 = df->sps->a2;
    df->a3 = df->sps->a3;
}
 
_DCL_CODE_ACCESS
void DCL_updateDF23NoCheck(DCL_DF23 *df)
{
    dcl_interrupt_t ints;
    
    ints = DCL_disableInts();
    DCL_forceUpdateDF23(df);
    DCL_restoreInts(ints);
}
 
_DCL_CODE_ACCESS
bool DCL_updateDF23(DCL_DF23 *df)
{
    if (DCL_setUpdateStatus(df))
    {
        DCL_updateDF23NoCheck(df);
        DCL_clearUpdateStatus(df);
        return true;
    }
    return false;
}
 
_DCL_CODE_ACCESS
bool DCL_isStableDF23(DCL_DF23 *df)
{
    return(DCL_isStablePn3(1.0f, df->sps->a1, df->sps->a2, df->sps->a3));
}
 
_DCL_CODE_ACCESS
void DCL_loadDF23asZPK(DCL_DF23 *df, DCL_ZPK3 *zpk)
{
#ifdef DCL_ERROR_HANDLING_ENABLED
    uint32_t err_code = dcl_none;
    err_code |= DCL_isZero(cimagf(zpk->z1) + cimagf(zpk->z2) + cimagf(zpk->z3)) ? dcl_none : dcl_param_invalid_err;
    err_code |= DCL_isZero(cimagf(zpk->p1) + cimagf(zpk->p2) + cimagf(zpk->p3)) ? dcl_none : dcl_param_invalid_err;
    if (err_code)
    {
        DCL_setError(df,err_code);
        DCL_getErrorInfo(df);
        DCL_runErrorHandler(df);
    }
#endif
 
    float32_t beta2 = -(float32_t) crealf(zpk->z1 + zpk->z2 + zpk->z3);
    float32_t beta1 = (float32_t) crealf((zpk->z1 * zpk->z2) + (zpk->z2 * zpk->z3) + (zpk->z1 * zpk->z3));
    float32_t beta0 = -(float32_t) crealf(zpk->z1 * zpk->z2 * zpk->z3);
 
    float32_t alpha2 = -(float32_t) crealf(zpk->p1 + zpk->p2 + zpk->p3);
    float32_t alpha1 = (float32_t) crealf((zpk->p1 * zpk->p2) + (zpk->p2 * zpk->p3) + (zpk->p1 * zpk->p3));
    float32_t alpha0 = -(float32_t) crealf(zpk->p1 * zpk->p2 * zpk->p3);
 
    float32_t T = df->css->T;
    float32_t a0p = 8.0f + (alpha2 * 4.0f * T) + (alpha1 * 2.0f * T * T) + (alpha0 * T * T * T);
 
    df->sps->b0 = zpk->K * (8.0f + (beta2 * 4.0f * T) + (beta1 * 2.0f * T * T) + (beta0 * T * T * T)) / a0p;
    df->sps->b1 = zpk->K * (-24.0f - (beta2 * 4.0f * T) + (beta1 * 2.0f * T * T) + (3.0f * beta0 * T * T * T)) / a0p;
    df->sps->b2 = zpk->K * (24.0f - (beta2 * 4.0f * T) - (beta1 * 2.0f * T * T) + (3.0f * beta0 * T * T * T)) / a0p;
    df->sps->b3 = zpk->K * (-8.0f + (beta2 * 4.0f * T) - (beta1 * 2.0f * T * T) + (beta0 * T * T * T)) / a0p;
 
    df->sps->a1 = (-24.0f - (alpha2 * 4.0f * T) + (alpha1 * 2.0f * T * T) + (3.0f * alpha0 * T * T * T)) / a0p;
    df->sps->a2 = (24.0f - (alpha2 * 4.0f * T) - (alpha1 * 2.0f * T * T) + (3.0f * alpha0 * T * T * T)) / a0p;
    df->sps->a3 = (-8.0f + (alpha2 * 4.0f * T) - (alpha1 * 2.0f * T * T) + (alpha0 * T * T * T)) / a0p;
}
 
_DCL_CRIT_ACCESS
float32_t DCL_runDF23(DCL_DF23 *df, float32_t ek)
{
    float32_t v7 = (ek * df->b0) + df->x1;
    df->x1 = (ek * df->b1) + df->x2 - (v7 * df->a1);
    df->x2 = (ek * df->b2) + df->x3 - (v7 * df->a2);
    df->x3 = (ek * df->b3) - (v7 * df->a3);
    return(v7);
}
 
_DCL_CRIT_ACCESS
float32_t DCL_runDF23PartialCompute(DCL_DF23 *df, float32_t ek)
{
    return((ek * df->b0) + df->x1);
}
 
_DCL_CRIT_ACCESS
void DCL_runDF23PartialUpdate(DCL_DF23 *df, float32_t ek, float32_t uk)
{
    df->x1 = (ek * df->b1) + df->x2 - (uk * df->a1);
    df->x2 = (ek * df->b2) + df->x3 - (uk * df->a2);
    df->x3 = (ek * df->b3) - (uk * df->a3);
}
 
_DCL_CRIT_ACCESS
float32_t DCL_runDF23Clamp(DCL_DF23 *df, float32_t ek, float32_t Umax, float32_t Umin)
{
    float32_t uk = DCL_runDF23PartialCompute(df, ek);
    bool is_clamped = DCL_runClamp(&uk, Umax, Umin);
    if(!is_clamped) DCL_runDF23PartialUpdate(df, ek, uk);
    return(uk);
}
 
#ifdef __cplusplus
}
#endif // extern "C"
 
#endif // _DCL_DF23_H_