dcl_df22.h

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#ifndef _DCL_DF22_H_
#define _DCL_DF22_H_
 
#ifdef __cplusplus
extern "C" {
#endif
 
#include "../dcl_common.h"
 
//--- Direct Form 2 - 2nd order ----------------------------------------------
 
typedef struct dcl_df22_sps
{
    float32_t b0;   
    float32_t b1;   
    float32_t b2;   
    float32_t a1;   
    float32_t a2;   
} DCL_DF22_SPS;
 
#define DF22_SPS_DEFAULTS { 1.0f, 0.0f, 0.0f, 0.0f, 0.0f }
 
typedef _DCL_VOLATILE struct dcl_df22
{
    /* compensator parameter */
    float32_t b0;   
    float32_t b1;   
    float32_t b2;   
    float32_t a1;   
    float32_t a2;   
 
    /* internal storage */
    float32_t x1;   
    float32_t x2;   
 
    /* miscellaneous */
    DCL_DF22_SPS *sps; 
    DCL_CSS *css;      
} DCL_DF22;
 
#define DF22_DEFAULTS { 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, \
        &(DCL_DF22_SPS)DF22_SPS_DEFAULTS, &(DCL_CSS)DCL_CSS_DEFAULTS }
 
#define DF22_INT_DEFAULTS .x1=0.0f, .x2=0.0f, .sps=&(DCL_DF22_SPS)DF22_SPS_DEFAULTS, \
                          .css=&(DCL_CSS)DCL_CSS_DEFAULTS 
                        
#define DCL_initDF22() &(DCL_DF22)DF22_DEFAULTS
 
#define DCL_initDF22asParam(_b0,_b1,_b2,_a1,_a2) &(DCL_DF22){ .b0=_b0, .b1=_b1, \
                        .b2=_b2, .a1=_a1, .a2=_a2, .a3=_a3, DF22_INT_DEFAULTS }
 
#define DCL_initDF22asSPS(df_ptr,sps_ptr)                                                \
({                                                                                       \
    DCL_DF22* new_df = (df_ptr) ? df_ptr : DCL_initDF22();                               \
    DCL_DF22_SPS* new_sps = (sps_ptr) ? sps_ptr : &(DCL_DF22_SPS)DF22_SPS_DEFAULTS;      \
    if(sps_ptr)                                                                          \
    {                                                                                    \
        *new_df = (DCL_DF22){ (new_sps)->b0, (new_sps)->b1, (new_sps)->b2, (new_sps)->a1,\
        (new_sps)->a2, 0.0f, 0.0f, (DCL_DF22_SPS*)new_sps, &(DCL_CSS)DCL_CSS_DEFAULTS }; \
    }                                                                                    \
    new_df;                                                                              \
})                    
 
_DCL_CODE_ACCESS
void DCL_resetDF22(DCL_DF22 *df)
{
    dcl_interrupt_t ints;
 
    ints = DCL_disableInts();
    df->x1 = df->x2 = 0.0f;
    DCL_restoreInts(ints);
}
 
_DCL_CODE_ACCESS
void DCL_forceUpdateDF22(DCL_DF22 *df)
{
    df->b0 = df->sps->b0;
    df->b1 = df->sps->b1;
    df->b2 = df->sps->b2;
    df->a1 = df->sps->a1;
    df->a2 = df->sps->a2;
}
 
_DCL_CODE_ACCESS
void DCL_updateDF22NoCheck(DCL_DF22 *df)
{
    dcl_interrupt_t ints;
    
    ints = DCL_disableInts();
    DCL_forceUpdateDF22(df);
    DCL_restoreInts(ints);
}
 
_DCL_CODE_ACCESS
bool DCL_updateDF22(DCL_DF22 *df)
{
    if (DCL_setUpdateStatus(df))
    {
        DCL_updateDF22NoCheck(df);
        DCL_clearUpdateStatus(df);
        return true;
    }
    return false;
}
 
_DCL_CODE_ACCESS
bool DCL_isStableDF22(DCL_DF22 *df)
{
    return(DCL_isStablePn2(1.0f, df->sps->a1, df->sps->a2));
}
 
_DCL_CODE_ACCESS
void DCL_loadDF22asZPK(DCL_DF22 *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)) ? dcl_none : dcl_param_invalid_err;
    err_code |= DCL_isZero(cimagf(zpk->p1) + cimagf(zpk->p2)) ? dcl_none : dcl_param_invalid_err;
    if (err_code)
    {
        DCL_setError(df,err_code);
        DCL_getErrorInfo(df);
        DCL_runErrorHandler(df);
    }
#endif
 
    float32_t beta1 = -(float32_t) crealf(zpk->z1 + zpk->z2);
    float32_t beta0 = (float32_t) crealf(zpk->z1 * zpk->z2);
    float32_t alpha1 = -(float32_t) crealf(zpk->p1 + zpk->p2);
    float32_t alpha0 = (float32_t) crealf(zpk->p1 * zpk->p2);
 
    float32_t T = df->css->T;
    float32_t a0p = 4.0f + (alpha1 * 2.0f * T) + (alpha0 * T * T);
 
    df->sps->b0 = zpk->K * (4.0f + (beta1 * 2.0f * T) + (beta0 * T * T)) / a0p;
    df->sps->b1 = zpk->K * (-8.0f + (2.0f * beta0 * T * T)) / a0p;
    df->sps->b2 = zpk->K * (4.0f - (beta1 * 2.0f * T) + (beta0 * T * T)) / a0p;
    df->sps->a1 = (-8.0f + (2.0f * alpha0 * T * T)) / a0p;
    df->sps->a2 = (4.0f - (alpha1 * 2.0f * T) + (alpha0 * T * T)) / a0p;
}
 
_DCL_CODE_ACCESS
void DCL_loadDF22asZwn(DCL_DF22 *df, float32_t z, float32_t wn)
{
 
#ifdef DCL_ERROR_HANDLING_ENABLED
    uint32_t err_code = dcl_none;
    err_code |= (z >= 0.0f) ? dcl_none : dcl_param_invalid_err;
    err_code |= (wn >= 0.0f) ? dcl_none : dcl_param_invalid_err;
    if (err_code)
    {
        DCL_setError(df,err_code);
        DCL_getErrorInfo(df);
        DCL_runErrorHandler(df);
    }
#endif
 
    float32_t T = df->css->T;
    float32_t v1 = wn * wn * T * T;
    float32_t a2p = 1.0f / (4.0f + (4.0f * z * wn * T) + v1);
    df->sps->b0 = v1 * a2p;
    df->sps->b1 = 2.0f * df->sps->b0;
    df->sps->b2 = df->sps->b0;
    df->sps->a1 = ((2.0f * v1) - 8.0f) * a2p;
    df->sps->a2 = (4.0f - (4.0f * z * wn * T) + v1) * a2p;
}
 
_DCL_CODE_ACCESS
void DCL_loadDF22asSeriesPID(DCL_DF22 *df, float32_t Kp, float32_t Ki, float32_t Kd, float32_t fc)
{
 
#ifdef DCL_ERROR_HANDLING_ENABLED
    uint32_t err_code = dcl_none;
    err_code |= (Kp < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= (Ki < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= (Kd < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= ((fc < 0.0f) || (fc > (1.0f / (2.0f * df->css->T)))) ? dcl_param_range_err : dcl_none;
    if (err_code)
    {
        DCL_setError(df,err_code);
        DCL_getErrorInfo(df);
        DCL_runErrorHandler(df);
    }
#endif
 
    float32_t T = df->css->T;
    float32_t tau = 1 / (2.0f * CONST_PI * fc);
    float32_t c1 = 2.0f / (T + (2.0f * tau));
    float32_t c2 = c1 * (T - (2.0f * tau)) / 2.0f;
    float32_t Kdp = Kd * c1;
    df->sps->b0 = Kp * (1 + Ki + Kdp);
    df->sps->b1 = Kp * (c2 - 1 + Ki*c2 - 2*Kdp);
    df->sps->b2 = Kp * (-c2 + Kdp);
    df->sps->a1 = c2 - 1;
    df->sps->a2 = -c2;
}
 
_DCL_CODE_ACCESS
void DCL_loadDF22asParallelPID(DCL_DF22 *df, float32_t Kp, float32_t Ki, float32_t Kd, float32_t fc)
{
 
#ifdef DCL_ERROR_HANDLING_ENABLED
    uint32_t err_code = dcl_none;
    err_code |= (Kp < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= (Ki < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= (Kd < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= (fc < 0.0f) ? dcl_param_range_err : dcl_none;
    err_code |= (fc > (1.0f / (2.0f * df->css->T))) ? dcl_param_warn_err : dcl_none;
    if (err_code)
    {
        DCL_setError(df,err_code);
        DCL_getErrorInfo(df);
        DCL_runErrorHandler(df);
    }
#endif
 
    float32_t T = df->css->T;
    float32_t tau = 1.0f / (2.0f * CONST_PI * fc);
    float32_t c1 = 2.0f / (T + (2.0f * tau));
    float32_t c2 = c1 * (T - (2.0f * tau)) / 2.0f;
    float32_t Kdp = Kd * c1;
    df->sps->b0 = Kp + Ki + Kdp;
    df->sps->b1 = (Kp * (c2 - 1)) + (Ki * c2) - (2.0f * Kdp);
    df->sps->b2 = (-c2 * Kp) + Kdp;
    df->sps->a1 = c2 - 1;
    df->sps->a2 = -c2;
}
 
_DCL_CRIT_ACCESS
float32_t DCL_runDF22(DCL_DF22 *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) - (v7 * df->a2);
 
    return(v7);
}
 
_DCL_CRIT_ACCESS
float32_t DCL_runDF22PartialCompute(DCL_DF22 *df, float32_t ek)
{
    return((ek * df->b0) + df->x1);
}
 
_DCL_CRIT_ACCESS
void DCL_runDF22PartialUpdate(DCL_DF22 *df, float32_t ek, float32_t uk)
{
    df->x1 = (ek * df->b1) + df->x2 - (uk * df->a1);
    df->x2 = (ek * df->b2) - (uk * df->a2);
}
 
_DCL_CRIT_ACCESS
float32_t DCL_runDF22Clamp(DCL_DF22 *df, float32_t ek, float32_t Umax, float32_t Umin)
{
    float32_t uk = DCL_runDF22PartialCompute(df, ek);
    bool is_clamped = DCL_runClamp(&uk, Umax, Umin);
    if(!is_clamped) DCL_runDF22PartialUpdate(df, ek, uk);
    return(uk);
}
 
#ifdef __cplusplus
}
#endif // extern "C"
 
#endif // _DCL_DF22_H_