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Removed error on fat32 library, seems now to be able navigate among sectors in...
Removed error on fat32 library, seems now to be able navigate among sectors in both directions. Improved SDLCD drawing performances by almost 1000x.
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arm_biquad_cascade_df1_q15.c
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/ lib / src / stm32f4 / CPU / CMSIS / DSP_Lib / Source / FilteringFunctions / arm_biquad_cascade_df1_q15.c
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jeandet@pc-de-jeandet3.LAB-LPP.LOCAL
Added ARM CMSIS for fast math and circle drawing function for ili9328 driver.
 r41 /* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 15. July 2011
* $Revision: V1.0.10
*
* Project: CMSIS DSP Library
* Title: arm_biquad_cascade_df1_q15.c
*
* Description: Processing function for the
* Q15 Biquad cascade DirectFormI(DF1) filter.
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
* Version 1.0.10 2011/7/15
* Big Endian support added and Merged M0 and M3/M4 Source code.
*
* Version 1.0.3 2010/11/29
* Re-organized the CMSIS folders and updated documentation.
*
* Version 1.0.2 2010/11/11
* Documentation updated.
*
* Version 1.0.1 2010/10/05
* Production release and review comments incorporated.
*
* Version 1.0.0 2010/09/20
* Production release and review comments incorporated.
*
* Version 0.0.5 2010/04/26
* incorporated review comments and updated with latest CMSIS layer
*
* Version 0.0.3 2010/03/10
* Initial version
* -------------------------------------------------------------------- */
#include "arm_math.h"
/**
* @ingroup groupFilters
*/
/**
* @addtogroup BiquadCascadeDF1
* @{
*/
/**
* @brief Processing function for the Q15 Biquad cascade filter.
* @param[in] *S points to an instance of the Q15 Biquad cascade structure.
* @param[in] *pSrc points to the block of input data.
* @param[out] *pDst points to the location where the output result is written.
* @param[in] blockSize number of samples to process per call.
* @return none.
*
*
* <b>Scaling and Overflow Behavior:</b>
* \par
* The function is implemented using a 64-bit internal accumulator.
* Both coefficients and state variables are represented in 1.15 format and multiplications yield a 2.30 result.
* The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format.
* There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved.
* The accumulator is then shifted by <code>postShift</code> bits to truncate the result to 1.15 format by discarding the low 16 bits.
* Finally, the result is saturated to 1.15 format.
*
* \par
* Refer to the function <code>arm_biquad_cascade_df1_fast_q15()</code> for a faster but less precise implementation of this filter for Cortex-M3 and Cortex-M4.
*/
void arm_biquad_cascade_df1_q15(
const arm_biquad_casd_df1_inst_q15 * S,
q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
{
#ifndef ARM_MATH_CM0
/* Run the below code for Cortex-M4 and Cortex-M3 */
q15_t *pIn = pSrc; /* Source pointer */
q15_t *pOut = pDst; /* Destination pointer */
q31_t in; /* Temporary variable to hold input value */
q31_t out; /* Temporary variable to hold output value */
q31_t b0; /* Temporary variable to hold bo value */
q31_t b1, a1; /* Filter coefficients */
q31_t state_in, state_out; /* Filter state variables */
q63_t acc; /* Accumulator */
int32_t shift = (15 - (int32_t) S->postShift); /* Post shift */
q15_t *pState = S->pState; /* State pointer */
q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
q31_t *pState_q31; /* 32-bit state pointer for SIMD implementation */
uint32_t sample, stage = (uint32_t) S->numStages; /* Stage loop counter */
do
{
/* Initialize state pointer of type q31 */
pState_q31 = (q31_t *) (pState);
/* Read the b0 and 0 coefficients using SIMD */
b0 = *__SIMD32(pCoeffs)++;
/* Read the b1 and b2 coefficients using SIMD */
b1 = *__SIMD32(pCoeffs)++;
/* Read the a1 and a2 coefficients using SIMD */
a1 = *__SIMD32(pCoeffs)++;
/* Read the input state values from the state buffer: x[n-1], x[n-2] */
state_in = (q31_t) (*pState_q31++);
/* Read the output state values from the state buffer: y[n-1], y[n-2] */
state_out = (q31_t) (*pState_q31);
/* Apply loop unrolling and compute 2 output values simultaneously. */
/* The variable acc hold output values that are being computed:
*
* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2]
* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2]
*/
sample = blockSize >> 1u;
/* First part of the processing with loop unrolling. Compute 2 outputs at a time.
** a second loop below computes the remaining 1 sample. */
while(sample > 0u)
{
/* Read the input */
in = *__SIMD32(pIn)++;
/* out = b0 * x[n] + 0 * 0 */
out = __SMUAD(b0, in);
/* acc += b1 * x[n-1] + b2 * x[n-2] + out */
acc = __SMLALD(b1, state_in, out);
/* acc += a1 * y[n-1] + a2 * y[n-2] */
acc = __SMLALD(a1, state_out, acc);
/* The result is converted from 3.29 to 1.31 if postShift = 1, and then saturation is applied */
out = __SSAT((acc >> shift), 16);
/* Every time after the output is computed state should be updated. */
/* The states should be updated as: */
/* Xn2 = Xn1 */
/* Xn1 = Xn */
/* Yn2 = Yn1 */
/* Yn1 = acc */
/* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */
/* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */
#ifndef ARM_MATH_BIG_ENDIAN
state_in = __PKHBT(in, state_in, 16);
state_out = __PKHBT(out, state_out, 16);
#else
state_in = __PKHBT(state_in >> 16, (in >> 16), 16);
state_out = __PKHBT(state_out >> 16, (out), 16);
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
/* out = b0 * x[n] + 0 * 0 */
out = __SMUADX(b0, in);
/* acc += b1 * x[n-1] + b2 * x[n-2] + out */
acc = __SMLALD(b1, state_in, out);
/* acc += a1 * y[n-1] + a2 * y[n-2] */
acc = __SMLALD(a1, state_out, acc);
/* The result is converted from 3.29 to 1.31 if postShift = 1, and then saturation is applied */
out = __SSAT((acc >> shift), 16);
/* Store the output in the destination buffer. */
#ifndef ARM_MATH_BIG_ENDIAN
*__SIMD32(pOut)++ = __PKHBT(state_out, out, 16);
#else
*__SIMD32(pOut)++ = __PKHBT(out, state_out >> 16, 16);
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
/* Every time after the output is computed state should be updated. */
/* The states should be updated as: */
/* Xn2 = Xn1 */
/* Xn1 = Xn */
/* Yn2 = Yn1 */
/* Yn1 = acc */
/* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */
/* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */
#ifndef ARM_MATH_BIG_ENDIAN
state_in = __PKHBT(in >> 16, state_in, 16);
state_out = __PKHBT(out, state_out, 16);
#else
state_in = __PKHBT(state_in >> 16, in, 16);
state_out = __PKHBT(state_out >> 16, out, 16);
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
/* Decrement the loop counter */
sample--;
}
/* If the blockSize is not a multiple of 2, compute any remaining output samples here.
** No loop unrolling is used. */
if((blockSize & 0x1u) != 0u)
{
/* Read the input */
in = *pIn++;
/* out = b0 * x[n] + 0 * 0 */
#ifndef ARM_MATH_BIG_ENDIAN
out = __SMUAD(b0, in);
#else
out = __SMUADX(b0, in);
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
/* acc = b1 * x[n-1] + b2 * x[n-2] + out */
acc = __SMLALD(b1, state_in, out);
/* acc += a1 * y[n-1] + a2 * y[n-2] */
acc = __SMLALD(a1, state_out, acc);
/* The result is converted from 3.29 to 1.31 if postShift = 1, and then saturation is applied */
out = __SSAT((acc >> shift), 16);
/* Store the output in the destination buffer. */
*pOut++ = (q15_t) out;
/* Every time after the output is computed state should be updated. */
/* The states should be updated as: */
/* Xn2 = Xn1 */
/* Xn1 = Xn */
/* Yn2 = Yn1 */
/* Yn1 = acc */
/* x[n-N], x[n-N-1] are packed together to make state_in of type q31 */
/* y[n-N], y[n-N-1] are packed together to make state_out of type q31 */
#ifndef ARM_MATH_BIG_ENDIAN
state_in = __PKHBT(in, state_in, 16);
state_out = __PKHBT(out, state_out, 16);
#else
state_in = __PKHBT(state_in >> 16, in, 16);
state_out = __PKHBT(state_out >> 16, out, 16);
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
}
/* The first stage goes from the input wire to the output wire. */
/* Subsequent numStages occur in-place in the output wire */
pIn = pDst;
/* Reset the output pointer */
pOut = pDst;
/* Store the updated state variables back into the state array */
*__SIMD32(pState)++ = state_in;
*__SIMD32(pState)++ = state_out;
/* Decrement the loop counter */
stage--;
} while(stage > 0u);
#else
/* Run the below code for Cortex-M0 */
q15_t *pIn = pSrc; /* Source pointer */
q15_t *pOut = pDst; /* Destination pointer */
q15_t b0, b1, b2, a1, a2; /* Filter coefficients */
q15_t Xn1, Xn2, Yn1, Yn2; /* Filter state variables */
q15_t Xn; /* temporary input */
q63_t acc; /* Accumulator */
int32_t shift = (15 - (int32_t) S->postShift); /* Post shift */
q15_t *pState = S->pState; /* State pointer */
q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
uint32_t sample, stage = (uint32_t) S->numStages; /* Stage loop counter */
do
{
/* Reading the coefficients */
b0 = *pCoeffs++;
b1 = *pCoeffs++;
b2 = *pCoeffs++;
a1 = *pCoeffs++;
a2 = *pCoeffs++;
/* Reading the state values */
Xn1 = pState[0];
Xn2 = pState[1];
Yn1 = pState[2];
Yn2 = pState[3];
/* The variables acc holds the output value that is computed:
* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2]
*/
sample = blockSize;
while(sample > 0u)
{
/* Read the input */
Xn = *pIn++;
/* acc = b0 * x[n] + b1 * x[n-1] + b2 * x[n-2] + a1 * y[n-1] + a2 * y[n-2] */
/* acc = b0 * x[n] */
acc = (q31_t) b0 *Xn;
/* acc += b1 * x[n-1] */
acc += (q31_t) b1 *Xn1;
/* acc += b[2] * x[n-2] */
acc += (q31_t) b2 *Xn2;
/* acc += a1 * y[n-1] */
acc += (q31_t) a1 *Yn1;
/* acc += a2 * y[n-2] */
acc += (q31_t) a2 *Yn2;
/* The result is converted to 1.31 */
acc = __SSAT((acc >> shift), 16);
/* Every time after the output is computed state should be updated. */
/* The states should be updated as: */
/* Xn2 = Xn1 */
/* Xn1 = Xn */
/* Yn2 = Yn1 */
/* Yn1 = acc */
Xn2 = Xn1;
Xn1 = Xn;
Yn2 = Yn1;
Yn1 = (q15_t) acc;
/* Store the output in the destination buffer. */
*pOut++ = (q15_t) acc;
/* decrement the loop counter */
sample--;
}
/* The first stage goes from the input buffer to the output buffer. */
/* Subsequent stages occur in-place in the output buffer */
pIn = pDst;
/* Reset to destination pointer */
pOut = pDst;
/* Store the updated state variables back into the pState array */
*pState++ = Xn1;
*pState++ = Xn2;
*pState++ = Yn1;
*pState++ = Yn2;
} while(--stage);
#endif /* #ifndef ARM_MATH_CM0 */
}
/**
* @} end of BiquadCascadeDF1 group
*/