Embedded Software and Motor Control Libraries for PXR40xx

Function GDFLIB_FilterFIRInit_F16
4.3.3 Return
void
4.3.4 Description
The function performs the initialization procedure for the GDFLIB_FilterFIR_F16
function. In particular, the function performs the following operations:
1. Resets the input buffer index to zero.
2. Initializes the input buffer pointer to the pointer provided as an argument.
3. Resets the input buffer.
After initialization, made by the function, the parameters and state structures should be
provided as arguments to calls of the GDFLIB_FilterFIR_F16 function.
Note
The input buffer pointer (State->pInBuf) must point to a Read/
Write memory region, which must be at least the number of the
filter taps long. The number of taps in a filter is equal to the
filter order + 1. There is no restriction as to the location of the
parameters structure as long as it is readable.
CAUTION
No check is performed for R/W capability and the length of the
input buffer (pState->pInBuf).
4.3.5 Re-entrancy
The function is re-entrant only if the calling code is provided with a distinct instance of
the structure pointed to by pState.
4.3.6 Code Example
#include "gdflib.h"
#define FIR_NUMTAPS 16
#define FIR_NUMTAPS_MAX 64
#define FIR_ORDER (FIR_NUMTAPS - 1)
GDFLIB_FILTERFIR_PARAM_T_F16 Param;
GDFLIB_FILTERFIR_STATE_T_F16 State;
tFrac16 f16InBuf[FIR_NUMTAPS_MAX];
Embedded Software and Motor Control Libraries for PXR40xx, Rev. 1.0
156 Freescale Semiconductor, Inc.