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Diffstat (limited to 'tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FastMathFunctions/arm_sin_q15.c')
| -rw-r--r-- | tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FastMathFunctions/arm_sin_q15.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FastMathFunctions/arm_sin_q15.c b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FastMathFunctions/arm_sin_q15.c new file mode 100644 index 0000000000..6bbacc634a --- /dev/null +++ b/tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/FastMathFunctions/arm_sin_q15.c @@ -0,0 +1,216 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2013 ARM Limited. All rights reserved. +* +* $Date: 17. January 2013 +* $Revision: V1.4.1 +* +* Project: CMSIS DSP Library +* Title: arm_sin_q15.c +* +* Description: Fast sine calculation for Q15 values. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Redistribution and use in source and binary forms, with or without +* modification, are permitted provided that the following conditions +* are met: +* - Redistributions of source code must retain the above copyright +* notice, this list of conditions and the following disclaimer. +* - Redistributions in binary form must reproduce the above copyright +* notice, this list of conditions and the following disclaimer in +* the documentation and/or other materials provided with the +* distribution. +* - Neither the name of ARM LIMITED nor the names of its contributors +* may be used to endorse or promote products derived from this +* software without specific prior written permission. +* +* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +* POSSIBILITY OF SUCH DAMAGE. +* -------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupFastMath + */ + + /** + * @addtogroup sin + * @{ + */ + + +/** +* \par + * Table values are in Q15 (1.15 fixed-point format) and generation is done in + * three steps. First, generate sin values in floating point: + * <pre> + * tableSize = 256; + * for(n = -1; n < (tableSize + 1); n++) + * { + * sinTable[n+1]= sin(2*pi*n/tableSize); + * } </pre> + * where pi value is 3.14159265358979 + * \par + * Second, convert floating-point to Q15 (fixed-point): + * (sinTable[i] * pow(2, 15)) + * \par + * Finally, round to the nearest integer value: + * sinTable[i] += (sinTable[i] > 0 ? 0.5 :-0.5); +*/ + +static const q15_t sinTableQ15[259] = { + 0xfcdc, 0x0, 0x324, 0x648, 0x96b, 0xc8c, 0xfab, 0x12c8, + 0x15e2, 0x18f9, 0x1c0c, 0x1f1a, 0x2224, 0x2528, 0x2827, 0x2b1f, + 0x2e11, 0x30fc, 0x33df, 0x36ba, 0x398d, 0x3c57, 0x3f17, 0x41ce, + 0x447b, 0x471d, 0x49b4, 0x4c40, 0x4ec0, 0x5134, 0x539b, 0x55f6, + 0x5843, 0x5a82, 0x5cb4, 0x5ed7, 0x60ec, 0x62f2, 0x64e9, 0x66d0, + 0x68a7, 0x6a6e, 0x6c24, 0x6dca, 0x6f5f, 0x70e3, 0x7255, 0x73b6, + 0x7505, 0x7642, 0x776c, 0x7885, 0x798a, 0x7a7d, 0x7b5d, 0x7c2a, + 0x7ce4, 0x7d8a, 0x7e1e, 0x7e9d, 0x7f0a, 0x7f62, 0x7fa7, 0x7fd9, + 0x7ff6, 0x7fff, 0x7ff6, 0x7fd9, 0x7fa7, 0x7f62, 0x7f0a, 0x7e9d, + 0x7e1e, 0x7d8a, 0x7ce4, 0x7c2a, 0x7b5d, 0x7a7d, 0x798a, 0x7885, + 0x776c, 0x7642, 0x7505, 0x73b6, 0x7255, 0x70e3, 0x6f5f, 0x6dca, + 0x6c24, 0x6a6e, 0x68a7, 0x66d0, 0x64e9, 0x62f2, 0x60ec, 0x5ed7, + 0x5cb4, 0x5a82, 0x5843, 0x55f6, 0x539b, 0x5134, 0x4ec0, 0x4c40, + 0x49b4, 0x471d, 0x447b, 0x41ce, 0x3f17, 0x3c57, 0x398d, 0x36ba, + 0x33df, 0x30fc, 0x2e11, 0x2b1f, 0x2827, 0x2528, 0x2224, 0x1f1a, + 0x1c0c, 0x18f9, 0x15e2, 0x12c8, 0xfab, 0xc8c, 0x96b, 0x648, + 0x324, 0x0, 0xfcdc, 0xf9b8, 0xf695, 0xf374, 0xf055, 0xed38, + 0xea1e, 0xe707, 0xe3f4, 0xe0e6, 0xdddc, 0xdad8, 0xd7d9, 0xd4e1, + 0xd1ef, 0xcf04, 0xcc21, 0xc946, 0xc673, 0xc3a9, 0xc0e9, 0xbe32, + 0xbb85, 0xb8e3, 0xb64c, 0xb3c0, 0xb140, 0xaecc, 0xac65, 0xaa0a, + 0xa7bd, 0xa57e, 0xa34c, 0xa129, 0x9f14, 0x9d0e, 0x9b17, 0x9930, + 0x9759, 0x9592, 0x93dc, 0x9236, 0x90a1, 0x8f1d, 0x8dab, 0x8c4a, + 0x8afb, 0x89be, 0x8894, 0x877b, 0x8676, 0x8583, 0x84a3, 0x83d6, + 0x831c, 0x8276, 0x81e2, 0x8163, 0x80f6, 0x809e, 0x8059, 0x8027, + 0x800a, 0x8000, 0x800a, 0x8027, 0x8059, 0x809e, 0x80f6, 0x8163, + 0x81e2, 0x8276, 0x831c, 0x83d6, 0x84a3, 0x8583, 0x8676, 0x877b, + 0x8894, 0x89be, 0x8afb, 0x8c4a, 0x8dab, 0x8f1d, 0x90a1, 0x9236, + 0x93dc, 0x9592, 0x9759, 0x9930, 0x9b17, 0x9d0e, 0x9f14, 0xa129, + 0xa34c, 0xa57e, 0xa7bd, 0xaa0a, 0xac65, 0xaecc, 0xb140, 0xb3c0, + 0xb64c, 0xb8e3, 0xbb85, 0xbe32, 0xc0e9, 0xc3a9, 0xc673, 0xc946, + 0xcc21, 0xcf04, 0xd1ef, 0xd4e1, 0xd7d9, 0xdad8, 0xdddc, 0xe0e6, + 0xe3f4, 0xe707, 0xea1e, 0xed38, 0xf055, 0xf374, 0xf695, 0xf9b8, + 0xfcdc, 0x0, 0x324 +}; + + +/** + * @brief Fast approximation to the trigonometric sine function for Q15 data. + * @param[in] x Scaled input value in radians. + * @return sin(x). + * + * The Q15 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*pi). + */ + +q15_t arm_sin_q15( + q15_t x) +{ + q31_t sinVal; /* Temporary variables output */ + q15_t *tablePtr; /* Pointer to table */ + q15_t fract, in, in2; /* Temporary variables for input, output */ + q31_t wa, wb, wc, wd; /* Cubic interpolation coefficients */ + q15_t a, b, c, d; /* Four nearest output values */ + q15_t fractCube, fractSquare; /* Temporary values for fractional value */ + q15_t oneBy6 = 0x1555; /* Fixed point value of 1/6 */ + q15_t tableSpacing = TABLE_SPACING_Q15; /* Table spacing */ + int32_t index; /* Index variable */ + + in = x; + + /* Calculate the nearest index */ + index = (int32_t) in / tableSpacing; + + /* Calculate the nearest value of input */ + in2 = (q15_t) ((index) * tableSpacing); + + /* Calculation of fractional value */ + fract = (in - in2) << 8; + + /* fractSquare = fract * fract */ + fractSquare = (q15_t) ((fract * fract) >> 15); + + /* fractCube = fract * fract * fract */ + fractCube = (q15_t) ((fractSquare * fract) >> 15); + + /* Checking min and max index of table */ + if(index < 0) + { + index = 0; + } + else if(index > 256) + { + index = 256; + } + + /* Initialise table pointer */ + tablePtr = (q15_t *) & sinTableQ15[index]; + + /* Cubic interpolation process */ + /* Calculation of wa */ + /* wa = -(oneBy6)*fractCube + (fractSquare >> 1u) - (0x2AAA)*fract; */ + wa = (q31_t) oneBy6 *fractCube; + wa += (q31_t) 0x2AAA *fract; + wa = -(wa >> 15); + wa += ((q31_t) fractSquare >> 1u); + + /* Read first nearest value of output from the sin table */ + a = *tablePtr++; + + /* sinVal = a * wa */ + sinVal = a * wa; + + /* Calculation of wb */ + wb = (((q31_t) fractCube >> 1u) - (q31_t) fractSquare) - + (((q31_t) fract >> 1u) - 0x7FFF); + + /* Read second nearest value of output from the sin table */ + b = *tablePtr++; + + /* sinVal += b*wb */ + sinVal += b * wb; + + + /* Calculation of wc */ + wc = -(q31_t) fractCube + fractSquare; + wc = (wc >> 1u) + fract; + + /* Read third nearest value of output from the sin table */ + c = *tablePtr++; + + /* sinVal += c*wc */ + sinVal += c * wc; + + /* Calculation of wd */ + /* wd = (oneBy6)*fractCube - (oneBy6)*fract; */ + fractCube = fractCube - fract; + wd = ((q15_t) (((q31_t) oneBy6 * fractCube) >> 15)); + + /* Read fourth nearest value of output from the sin table */ + d = *tablePtr++; + + /* sinVal += d*wd; */ + sinVal += d * wd; + + /* Convert output value in 1.15(q15) format and saturate */ + sinVal = __SSAT((sinVal >> 15), 16); + + /* Return the output value in 1.15(q15) format */ + return ((q15_t) sinVal); + +} + +/** + * @} end of sin group + */ |