diff options
Diffstat (limited to 'fw/hid-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_q15.c')
| -rw-r--r-- | fw/hid-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_q15.c | 679 |
1 files changed, 0 insertions, 679 deletions
diff --git a/fw/hid-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_q15.c b/fw/hid-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_q15.c deleted file mode 100644 index a979783..0000000 --- a/fw/hid-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_fir_q15.c +++ /dev/null @@ -1,679 +0,0 @@ -/* ----------------------------------------------------------------------
- * Project: CMSIS DSP Library
- * Title: arm_fir_q15.c
- * Description: Q15 FIR filter processing function
- *
- * $Date: 27. January 2017
- * $Revision: V.1.5.1
- *
- * Target Processor: Cortex-M cores
- * -------------------------------------------------------------------- */
-/*
- * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
- *
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the License); you may
- * not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an AS IS BASIS, WITHOUT
- * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include "arm_math.h"
-
-/**
- * @ingroup groupFilters
- */
-
-/**
- * @addtogroup FIR
- * @{
- */
-
-/**
- * @brief Processing function for the Q15 FIR filter.
- * @param[in] *S points to an instance of the Q15 FIR structure.
- * @param[in] *pSrc points to the block of input data.
- * @param[out] *pDst points to the block of output data.
- * @param[in] blockSize number of samples to process per call.
- * @return none.
- *
- *
- * \par Restrictions
- * If the silicon does not support unaligned memory access enable the macro UNALIGNED_SUPPORT_DISABLE
- * In this case input, output, state buffers should be aligned by 32-bit
- *
- * <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.
- * After all additions have been performed, the accumulator is truncated to 34.15 format by discarding low 15 bits.
- * Lastly, the accumulator is saturated to yield a result in 1.15 format.
- *
- * \par
- * Refer to the function <code>arm_fir_fast_q15()</code> for a faster but less precise implementation of this function.
- */
-
-#if defined (ARM_MATH_DSP)
-
-/* Run the below code for Cortex-M4 and Cortex-M3 */
-
-#ifndef UNALIGNED_SUPPORT_DISABLE
-
-
-void arm_fir_q15(
- const arm_fir_instance_q15 * S,
- q15_t * pSrc,
- q15_t * pDst,
- uint32_t blockSize)
-{
- q15_t *pState = S->pState; /* State pointer */
- q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
- q15_t *pStateCurnt; /* Points to the current sample of the state */
- q15_t *px1; /* Temporary q15 pointer for state buffer */
- q15_t *pb; /* Temporary pointer for coefficient buffer */
- q31_t x0, x1, x2, x3, c0; /* Temporary variables to hold SIMD state and coefficient values */
- q63_t acc0, acc1, acc2, acc3; /* Accumulators */
- uint32_t numTaps = S->numTaps; /* Number of taps in the filter */
- uint32_t tapCnt, blkCnt; /* Loop counters */
-
-
- /* S->pState points to state array which contains previous frame (numTaps - 1) samples */
- /* pStateCurnt points to the location where the new input data should be written */
- pStateCurnt = &(S->pState[(numTaps - 1U)]);
-
- /* Apply loop unrolling and compute 4 output values simultaneously.
- * The variables acc0 ... acc3 hold output values that are being computed:
- *
- * acc0 = b[numTaps-1] * x[n-numTaps-1] + b[numTaps-2] * x[n-numTaps-2] + b[numTaps-3] * x[n-numTaps-3] +...+ b[0] * x[0]
- * acc1 = b[numTaps-1] * x[n-numTaps] + b[numTaps-2] * x[n-numTaps-1] + b[numTaps-3] * x[n-numTaps-2] +...+ b[0] * x[1]
- * acc2 = b[numTaps-1] * x[n-numTaps+1] + b[numTaps-2] * x[n-numTaps] + b[numTaps-3] * x[n-numTaps-1] +...+ b[0] * x[2]
- * acc3 = b[numTaps-1] * x[n-numTaps+2] + b[numTaps-2] * x[n-numTaps+1] + b[numTaps-3] * x[n-numTaps] +...+ b[0] * x[3]
- */
-
- blkCnt = blockSize >> 2;
-
- /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
- ** a second loop below computes the remaining 1 to 3 samples. */
- while (blkCnt > 0U)
- {
- /* Copy four new input samples into the state buffer.
- ** Use 32-bit SIMD to move the 16-bit data. Only requires two copies. */
- *__SIMD32(pStateCurnt)++ = *__SIMD32(pSrc)++;
- *__SIMD32(pStateCurnt)++ = *__SIMD32(pSrc)++;
-
- /* Set all accumulators to zero */
- acc0 = 0;
- acc1 = 0;
- acc2 = 0;
- acc3 = 0;
-
- /* Initialize state pointer of type q15 */
- px1 = pState;
-
- /* Initialize coeff pointer of type q31 */
- pb = pCoeffs;
-
- /* Read the first two samples from the state buffer: x[n-N], x[n-N-1] */
- x0 = _SIMD32_OFFSET(px1);
-
- /* Read the third and forth samples from the state buffer: x[n-N-1], x[n-N-2] */
- x1 = _SIMD32_OFFSET(px1 + 1U);
-
- px1 += 2U;
-
- /* Loop over the number of taps. Unroll by a factor of 4.
- ** Repeat until we've computed numTaps-4 coefficients. */
- tapCnt = numTaps >> 2;
-
- while (tapCnt > 0U)
- {
- /* Read the first two coefficients using SIMD: b[N] and b[N-1] coefficients */
- c0 = *__SIMD32(pb)++;
-
- /* acc0 += b[N] * x[n-N] + b[N-1] * x[n-N-1] */
- acc0 = __SMLALD(x0, c0, acc0);
-
- /* acc1 += b[N] * x[n-N-1] + b[N-1] * x[n-N-2] */
- acc1 = __SMLALD(x1, c0, acc1);
-
- /* Read state x[n-N-2], x[n-N-3] */
- x2 = _SIMD32_OFFSET(px1);
-
- /* Read state x[n-N-3], x[n-N-4] */
- x3 = _SIMD32_OFFSET(px1 + 1U);
-
- /* acc2 += b[N] * x[n-N-2] + b[N-1] * x[n-N-3] */
- acc2 = __SMLALD(x2, c0, acc2);
-
- /* acc3 += b[N] * x[n-N-3] + b[N-1] * x[n-N-4] */
- acc3 = __SMLALD(x3, c0, acc3);
-
- /* Read coefficients b[N-2], b[N-3] */
- c0 = *__SIMD32(pb)++;
-
- /* acc0 += b[N-2] * x[n-N-2] + b[N-3] * x[n-N-3] */
- acc0 = __SMLALD(x2, c0, acc0);
-
- /* acc1 += b[N-2] * x[n-N-3] + b[N-3] * x[n-N-4] */
- acc1 = __SMLALD(x3, c0, acc1);
-
- /* Read state x[n-N-4], x[n-N-5] */
- x0 = _SIMD32_OFFSET(px1 + 2U);
-
- /* Read state x[n-N-5], x[n-N-6] */
- x1 = _SIMD32_OFFSET(px1 + 3U);
-
- /* acc2 += b[N-2] * x[n-N-4] + b[N-3] * x[n-N-5] */
- acc2 = __SMLALD(x0, c0, acc2);
-
- /* acc3 += b[N-2] * x[n-N-5] + b[N-3] * x[n-N-6] */
- acc3 = __SMLALD(x1, c0, acc3);
-
- px1 += 4U;
-
- tapCnt--;
-
- }
-
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps.
- ** This is always be 2 taps since the filter length is even. */
- if ((numTaps & 0x3U) != 0U)
- {
- /* Read 2 coefficients */
- c0 = *__SIMD32(pb)++;
-
- /* Fetch 4 state variables */
- x2 = _SIMD32_OFFSET(px1);
-
- x3 = _SIMD32_OFFSET(px1 + 1U);
-
- /* Perform the multiply-accumulates */
- acc0 = __SMLALD(x0, c0, acc0);
-
- px1 += 2U;
-
- acc1 = __SMLALD(x1, c0, acc1);
- acc2 = __SMLALD(x2, c0, acc2);
- acc3 = __SMLALD(x3, c0, acc3);
- }
-
- /* The results in the 4 accumulators are in 2.30 format. Convert to 1.15 with saturation.
- ** Then store the 4 outputs in the destination buffer. */
-
-#ifndef ARM_MATH_BIG_ENDIAN
-
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc0 >> 15), 16), __SSAT((acc1 >> 15), 16), 16);
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc2 >> 15), 16), __SSAT((acc3 >> 15), 16), 16);
-
-#else
-
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc1 >> 15), 16), __SSAT((acc0 >> 15), 16), 16);
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc3 >> 15), 16), __SSAT((acc2 >> 15), 16), 16);
-
-#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
-
-
-
- /* Advance the state pointer by 4 to process the next group of 4 samples */
- pState = pState + 4;
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
- ** No loop unrolling is used. */
- blkCnt = blockSize % 0x4U;
- while (blkCnt > 0U)
- {
- /* Copy two samples into state buffer */
- *pStateCurnt++ = *pSrc++;
-
- /* Set the accumulator to zero */
- acc0 = 0;
-
- /* Initialize state pointer of type q15 */
- px1 = pState;
-
- /* Initialize coeff pointer of type q31 */
- pb = pCoeffs;
-
- tapCnt = numTaps >> 1;
-
- do
- {
-
- c0 = *__SIMD32(pb)++;
- x0 = *__SIMD32(px1)++;
-
- acc0 = __SMLALD(x0, c0, acc0);
- tapCnt--;
- }
- while (tapCnt > 0U);
-
- /* The result is in 2.30 format. Convert to 1.15 with saturation.
- ** Then store the output in the destination buffer. */
- *pDst++ = (q15_t) (__SSAT((acc0 >> 15), 16));
-
- /* Advance state pointer by 1 for the next sample */
- pState = pState + 1;
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- /* Processing is complete.
- ** Now copy the last numTaps - 1 samples to the satrt of the state buffer.
- ** This prepares the state buffer for the next function call. */
-
- /* Points to the start of the state buffer */
- pStateCurnt = S->pState;
-
- /* Calculation of count for copying integer writes */
- tapCnt = (numTaps - 1U) >> 2;
-
- while (tapCnt > 0U)
- {
-
- /* Copy state values to start of state buffer */
- *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
- *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
-
- tapCnt--;
-
- }
-
- /* Calculation of count for remaining q15_t data */
- tapCnt = (numTaps - 1U) % 0x4U;
-
- /* copy remaining data */
- while (tapCnt > 0U)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-}
-
-#else /* UNALIGNED_SUPPORT_DISABLE */
-
-void arm_fir_q15(
- const arm_fir_instance_q15 * S,
- q15_t * pSrc,
- q15_t * pDst,
- uint32_t blockSize)
-{
- q15_t *pState = S->pState; /* State pointer */
- q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
- q15_t *pStateCurnt; /* Points to the current sample of the state */
- q63_t acc0, acc1, acc2, acc3; /* Accumulators */
- q15_t *pb; /* Temporary pointer for coefficient buffer */
- q15_t *px; /* Temporary q31 pointer for SIMD state buffer accesses */
- q31_t x0, x1, x2, c0; /* Temporary variables to hold SIMD state and coefficient values */
- uint32_t numTaps = S->numTaps; /* Number of taps in the filter */
- uint32_t tapCnt, blkCnt; /* Loop counters */
-
-
- /* S->pState points to state array which contains previous frame (numTaps - 1) samples */
- /* pStateCurnt points to the location where the new input data should be written */
- pStateCurnt = &(S->pState[(numTaps - 1U)]);
-
- /* Apply loop unrolling and compute 4 output values simultaneously.
- * The variables acc0 ... acc3 hold output values that are being computed:
- *
- * acc0 = b[numTaps-1] * x[n-numTaps-1] + b[numTaps-2] * x[n-numTaps-2] + b[numTaps-3] * x[n-numTaps-3] +...+ b[0] * x[0]
- * acc1 = b[numTaps-1] * x[n-numTaps] + b[numTaps-2] * x[n-numTaps-1] + b[numTaps-3] * x[n-numTaps-2] +...+ b[0] * x[1]
- * acc2 = b[numTaps-1] * x[n-numTaps+1] + b[numTaps-2] * x[n-numTaps] + b[numTaps-3] * x[n-numTaps-1] +...+ b[0] * x[2]
- * acc3 = b[numTaps-1] * x[n-numTaps+2] + b[numTaps-2] * x[n-numTaps+1] + b[numTaps-3] * x[n-numTaps] +...+ b[0] * x[3]
- */
-
- blkCnt = blockSize >> 2;
-
- /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
- ** a second loop below computes the remaining 1 to 3 samples. */
- while (blkCnt > 0U)
- {
- /* Copy four new input samples into the state buffer.
- ** Use 32-bit SIMD to move the 16-bit data. Only requires two copies. */
- *pStateCurnt++ = *pSrc++;
- *pStateCurnt++ = *pSrc++;
- *pStateCurnt++ = *pSrc++;
- *pStateCurnt++ = *pSrc++;
-
-
- /* Set all accumulators to zero */
- acc0 = 0;
- acc1 = 0;
- acc2 = 0;
- acc3 = 0;
-
- /* Typecast q15_t pointer to q31_t pointer for state reading in q31_t */
- px = pState;
-
- /* Typecast q15_t pointer to q31_t pointer for coefficient reading in q31_t */
- pb = pCoeffs;
-
- /* Read the first two samples from the state buffer: x[n-N], x[n-N-1] */
- x0 = *__SIMD32(px)++;
-
- /* Read the third and forth samples from the state buffer: x[n-N-2], x[n-N-3] */
- x2 = *__SIMD32(px)++;
-
- /* Loop over the number of taps. Unroll by a factor of 4.
- ** Repeat until we've computed numTaps-(numTaps%4) coefficients. */
- tapCnt = numTaps >> 2;
-
- while (tapCnt > 0)
- {
- /* Read the first two coefficients using SIMD: b[N] and b[N-1] coefficients */
- c0 = *__SIMD32(pb)++;
-
- /* acc0 += b[N] * x[n-N] + b[N-1] * x[n-N-1] */
- acc0 = __SMLALD(x0, c0, acc0);
-
- /* acc2 += b[N] * x[n-N-2] + b[N-1] * x[n-N-3] */
- acc2 = __SMLALD(x2, c0, acc2);
-
- /* pack x[n-N-1] and x[n-N-2] */
-#ifndef ARM_MATH_BIG_ENDIAN
- x1 = __PKHBT(x2, x0, 0);
-#else
- x1 = __PKHBT(x0, x2, 0);
-#endif
-
- /* Read state x[n-N-4], x[n-N-5] */
- x0 = _SIMD32_OFFSET(px);
-
- /* acc1 += b[N] * x[n-N-1] + b[N-1] * x[n-N-2] */
- acc1 = __SMLALDX(x1, c0, acc1);
-
- /* pack x[n-N-3] and x[n-N-4] */
-#ifndef ARM_MATH_BIG_ENDIAN
- x1 = __PKHBT(x0, x2, 0);
-#else
- x1 = __PKHBT(x2, x0, 0);
-#endif
-
- /* acc3 += b[N] * x[n-N-3] + b[N-1] * x[n-N-4] */
- acc3 = __SMLALDX(x1, c0, acc3);
-
- /* Read coefficients b[N-2], b[N-3] */
- c0 = *__SIMD32(pb)++;
-
- /* acc0 += b[N-2] * x[n-N-2] + b[N-3] * x[n-N-3] */
- acc0 = __SMLALD(x2, c0, acc0);
-
- /* Read state x[n-N-6], x[n-N-7] with offset */
- x2 = _SIMD32_OFFSET(px + 2U);
-
- /* acc2 += b[N-2] * x[n-N-4] + b[N-3] * x[n-N-5] */
- acc2 = __SMLALD(x0, c0, acc2);
-
- /* acc1 += b[N-2] * x[n-N-3] + b[N-3] * x[n-N-4] */
- acc1 = __SMLALDX(x1, c0, acc1);
-
- /* pack x[n-N-5] and x[n-N-6] */
-#ifndef ARM_MATH_BIG_ENDIAN
- x1 = __PKHBT(x2, x0, 0);
-#else
- x1 = __PKHBT(x0, x2, 0);
-#endif
-
- /* acc3 += b[N-2] * x[n-N-5] + b[N-3] * x[n-N-6] */
- acc3 = __SMLALDX(x1, c0, acc3);
-
- /* Update state pointer for next state reading */
- px += 4U;
-
- /* Decrement tap count */
- tapCnt--;
-
- }
-
- /* If the filter length is not a multiple of 4, compute the remaining filter taps.
- ** This is always be 2 taps since the filter length is even. */
- if ((numTaps & 0x3U) != 0U)
- {
-
- /* Read last two coefficients */
- c0 = *__SIMD32(pb)++;
-
- /* Perform the multiply-accumulates */
- acc0 = __SMLALD(x0, c0, acc0);
- acc2 = __SMLALD(x2, c0, acc2);
-
- /* pack state variables */
-#ifndef ARM_MATH_BIG_ENDIAN
- x1 = __PKHBT(x2, x0, 0);
-#else
- x1 = __PKHBT(x0, x2, 0);
-#endif
-
- /* Read last state variables */
- x0 = *__SIMD32(px);
-
- /* Perform the multiply-accumulates */
- acc1 = __SMLALDX(x1, c0, acc1);
-
- /* pack state variables */
-#ifndef ARM_MATH_BIG_ENDIAN
- x1 = __PKHBT(x0, x2, 0);
-#else
- x1 = __PKHBT(x2, x0, 0);
-#endif
-
- /* Perform the multiply-accumulates */
- acc3 = __SMLALDX(x1, c0, acc3);
- }
-
- /* The results in the 4 accumulators are in 2.30 format. Convert to 1.15 with saturation.
- ** Then store the 4 outputs in the destination buffer. */
-
-#ifndef ARM_MATH_BIG_ENDIAN
-
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc0 >> 15), 16), __SSAT((acc1 >> 15), 16), 16);
-
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc2 >> 15), 16), __SSAT((acc3 >> 15), 16), 16);
-
-#else
-
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc1 >> 15), 16), __SSAT((acc0 >> 15), 16), 16);
-
- *__SIMD32(pDst)++ =
- __PKHBT(__SSAT((acc3 >> 15), 16), __SSAT((acc2 >> 15), 16), 16);
-
-#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
-
- /* Advance the state pointer by 4 to process the next group of 4 samples */
- pState = pState + 4;
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
- ** No loop unrolling is used. */
- blkCnt = blockSize % 0x4U;
- while (blkCnt > 0U)
- {
- /* Copy two samples into state buffer */
- *pStateCurnt++ = *pSrc++;
-
- /* Set the accumulator to zero */
- acc0 = 0;
-
- /* Use SIMD to hold states and coefficients */
- px = pState;
- pb = pCoeffs;
-
- tapCnt = numTaps >> 1U;
-
- do
- {
- acc0 += (q31_t) * px++ * *pb++;
- acc0 += (q31_t) * px++ * *pb++;
- tapCnt--;
- }
- while (tapCnt > 0U);
-
- /* The result is in 2.30 format. Convert to 1.15 with saturation.
- ** Then store the output in the destination buffer. */
- *pDst++ = (q15_t) (__SSAT((acc0 >> 15), 16));
-
- /* Advance state pointer by 1 for the next sample */
- pState = pState + 1U;
-
- /* Decrement the loop counter */
- blkCnt--;
- }
-
- /* Processing is complete.
- ** Now copy the last numTaps - 1 samples to the satrt of the state buffer.
- ** This prepares the state buffer for the next function call. */
-
- /* Points to the start of the state buffer */
- pStateCurnt = S->pState;
-
- /* Calculation of count for copying integer writes */
- tapCnt = (numTaps - 1U) >> 2;
-
- while (tapCnt > 0U)
- {
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
- *pStateCurnt++ = *pState++;
-
- tapCnt--;
-
- }
-
- /* Calculation of count for remaining q15_t data */
- tapCnt = (numTaps - 1U) % 0x4U;
-
- /* copy remaining data */
- while (tapCnt > 0U)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-}
-
-
-#endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */
-
-#else /* ARM_MATH_CM0_FAMILY */
-
-
-/* Run the below code for Cortex-M0 */
-
-void arm_fir_q15(
- const arm_fir_instance_q15 * S,
- q15_t * pSrc,
- q15_t * pDst,
- uint32_t blockSize)
-{
- q15_t *pState = S->pState; /* State pointer */
- q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */
- q15_t *pStateCurnt; /* Points to the current sample of the state */
-
-
-
- q15_t *px; /* Temporary pointer for state buffer */
- q15_t *pb; /* Temporary pointer for coefficient buffer */
- q63_t acc; /* Accumulator */
- uint32_t numTaps = S->numTaps; /* Number of nTaps in the filter */
- uint32_t tapCnt, blkCnt; /* Loop counters */
-
- /* S->pState buffer contains previous frame (numTaps - 1) samples */
- /* pStateCurnt points to the location where the new input data should be written */
- pStateCurnt = &(S->pState[(numTaps - 1U)]);
-
- /* Initialize blkCnt with blockSize */
- blkCnt = blockSize;
-
- while (blkCnt > 0U)
- {
- /* Copy one sample at a time into state buffer */
- *pStateCurnt++ = *pSrc++;
-
- /* Set the accumulator to zero */
- acc = 0;
-
- /* Initialize state pointer */
- px = pState;
-
- /* Initialize Coefficient pointer */
- pb = pCoeffs;
-
- tapCnt = numTaps;
-
- /* Perform the multiply-accumulates */
- do
- {
- /* acc = b[numTaps-1] * x[n-numTaps-1] + b[numTaps-2] * x[n-numTaps-2] + b[numTaps-3] * x[n-numTaps-3] +...+ b[0] * x[0] */
- acc += (q31_t) * px++ * *pb++;
- tapCnt--;
- } while (tapCnt > 0U);
-
- /* The result is in 2.30 format. Convert to 1.15
- ** Then store the output in the destination buffer. */
- *pDst++ = (q15_t) __SSAT((acc >> 15U), 16);
-
- /* Advance state pointer by 1 for the next sample */
- pState = pState + 1;
-
- /* Decrement the samples loop counter */
- blkCnt--;
- }
-
- /* Processing is complete.
- ** Now copy the last numTaps - 1 samples to the satrt of the state buffer.
- ** This prepares the state buffer for the next function call. */
-
- /* Points to the start of the state buffer */
- pStateCurnt = S->pState;
-
- /* Copy numTaps number of values */
- tapCnt = (numTaps - 1U);
-
- /* copy data */
- while (tapCnt > 0U)
- {
- *pStateCurnt++ = *pState++;
-
- /* Decrement the loop counter */
- tapCnt--;
- }
-
-}
-
-#endif /* #if defined (ARM_MATH_DSP) */
-
-
-
-
-/**
- * @} end of FIR group
- */
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