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Diff: cmsis_dsp/FastMathFunctions/arm_sin_q31.c
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/FastMathFunctions/arm_sin_q31.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,240 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_sin_q31.c +* +* Description: Fast sine calculation for Q31 values. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* 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. +* -------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupFastMath + */ + + /** + * @addtogroup sin + * @{ + */ + +/** + * \par + * Tables generated are in Q31(1.31 Fixed point format) + * Generation of 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 + * Convert Floating point to Q31(Fixed point): + * (sinTable[i] * pow(2, 31)) + * \par + * rounding to nearest integer is done + * sinTable[i] += (sinTable[i] > 0 ? 0.5 :-0.5); + */ + +static const q31_t sinTableQ31[259] = { + 0xfcdbd541, 0x0, 0x3242abf, 0x647d97c, 0x96a9049, 0xc8bd35e, 0xfab272b, + 0x12c8106f, + 0x15e21445, 0x18f8b83c, 0x1c0b826a, 0x1f19f97b, 0x2223a4c5, 0x25280c5e, + 0x2826b928, 0x2b1f34eb, + 0x2e110a62, 0x30fbc54d, 0x33def287, 0x36ba2014, 0x398cdd32, 0x3c56ba70, + 0x3f1749b8, 0x41ce1e65, + 0x447acd50, 0x471cece7, 0x49b41533, 0x4c3fdff4, 0x4ebfe8a5, 0x5133cc94, + 0x539b2af0, 0x55f5a4d2, + 0x5842dd54, 0x5a82799a, 0x5cb420e0, 0x5ed77c8a, 0x60ec3830, 0x62f201ac, + 0x64e88926, 0x66cf8120, + 0x68a69e81, 0x6a6d98a4, 0x6c242960, 0x6dca0d14, 0x6f5f02b2, 0x70e2cbc6, + 0x72552c85, 0x73b5ebd1, + 0x7504d345, 0x7641af3d, 0x776c4edb, 0x78848414, 0x798a23b1, 0x7a7d055b, + 0x7b5d039e, 0x7c29fbee, + 0x7ce3ceb2, 0x7d8a5f40, 0x7e1d93ea, 0x7e9d55fc, 0x7f0991c4, 0x7f62368f, + 0x7fa736b4, 0x7fd8878e, + 0x7ff62182, 0x7fffffff, 0x7ff62182, 0x7fd8878e, 0x7fa736b4, 0x7f62368f, + 0x7f0991c4, 0x7e9d55fc, + 0x7e1d93ea, 0x7d8a5f40, 0x7ce3ceb2, 0x7c29fbee, 0x7b5d039e, 0x7a7d055b, + 0x798a23b1, 0x78848414, + 0x776c4edb, 0x7641af3d, 0x7504d345, 0x73b5ebd1, 0x72552c85, 0x70e2cbc6, + 0x6f5f02b2, 0x6dca0d14, + 0x6c242960, 0x6a6d98a4, 0x68a69e81, 0x66cf8120, 0x64e88926, 0x62f201ac, + 0x60ec3830, 0x5ed77c8a, + 0x5cb420e0, 0x5a82799a, 0x5842dd54, 0x55f5a4d2, 0x539b2af0, 0x5133cc94, + 0x4ebfe8a5, 0x4c3fdff4, + 0x49b41533, 0x471cece7, 0x447acd50, 0x41ce1e65, 0x3f1749b8, 0x3c56ba70, + 0x398cdd32, 0x36ba2014, + 0x33def287, 0x30fbc54d, 0x2e110a62, 0x2b1f34eb, 0x2826b928, 0x25280c5e, + 0x2223a4c5, 0x1f19f97b, + 0x1c0b826a, 0x18f8b83c, 0x15e21445, 0x12c8106f, 0xfab272b, 0xc8bd35e, + 0x96a9049, 0x647d97c, + 0x3242abf, 0x0, 0xfcdbd541, 0xf9b82684, 0xf6956fb7, 0xf3742ca2, 0xf054d8d5, + 0xed37ef91, + 0xea1debbb, 0xe70747c4, 0xe3f47d96, 0xe0e60685, 0xdddc5b3b, 0xdad7f3a2, + 0xd7d946d8, 0xd4e0cb15, + 0xd1eef59e, 0xcf043ab3, 0xcc210d79, 0xc945dfec, 0xc67322ce, 0xc3a94590, + 0xc0e8b648, 0xbe31e19b, + 0xbb8532b0, 0xb8e31319, 0xb64beacd, 0xb3c0200c, 0xb140175b, 0xaecc336c, + 0xac64d510, 0xaa0a5b2e, + 0xa7bd22ac, 0xa57d8666, 0xa34bdf20, 0xa1288376, 0x9f13c7d0, 0x9d0dfe54, + 0x9b1776da, 0x99307ee0, + 0x9759617f, 0x9592675c, 0x93dbd6a0, 0x9235f2ec, 0x90a0fd4e, 0x8f1d343a, + 0x8daad37b, 0x8c4a142f, + 0x8afb2cbb, 0x89be50c3, 0x8893b125, 0x877b7bec, 0x8675dc4f, 0x8582faa5, + 0x84a2fc62, 0x83d60412, + 0x831c314e, 0x8275a0c0, 0x81e26c16, 0x8162aa04, 0x80f66e3c, 0x809dc971, + 0x8058c94c, 0x80277872, + 0x8009de7e, 0x80000000, 0x8009de7e, 0x80277872, 0x8058c94c, 0x809dc971, + 0x80f66e3c, 0x8162aa04, + 0x81e26c16, 0x8275a0c0, 0x831c314e, 0x83d60412, 0x84a2fc62, 0x8582faa5, + 0x8675dc4f, 0x877b7bec, + 0x8893b125, 0x89be50c3, 0x8afb2cbb, 0x8c4a142f, 0x8daad37b, 0x8f1d343a, + 0x90a0fd4e, 0x9235f2ec, + 0x93dbd6a0, 0x9592675c, 0x9759617f, 0x99307ee0, 0x9b1776da, 0x9d0dfe54, + 0x9f13c7d0, 0xa1288376, + 0xa34bdf20, 0xa57d8666, 0xa7bd22ac, 0xaa0a5b2e, 0xac64d510, 0xaecc336c, + 0xb140175b, 0xb3c0200c, + 0xb64beacd, 0xb8e31319, 0xbb8532b0, 0xbe31e19b, 0xc0e8b648, 0xc3a94590, + 0xc67322ce, 0xc945dfec, + 0xcc210d79, 0xcf043ab3, 0xd1eef59e, 0xd4e0cb15, 0xd7d946d8, 0xdad7f3a2, + 0xdddc5b3b, 0xe0e60685, + 0xe3f47d96, 0xe70747c4, 0xea1debbb, 0xed37ef91, 0xf054d8d5, 0xf3742ca2, + 0xf6956fb7, 0xf9b82684, + 0xfcdbd541, 0x0, 0x3242abf +}; + + +/** + * @brief Fast approximation to the trigonometric sine function for Q31 data. + * @param[in] x Scaled input value in radians. + * @return sin(x). + * + * The Q31 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*pi), Here range excludes 2*pi. + */ + +q31_t arm_sin_q31( + q31_t x) +{ + q31_t sinVal, in, in2; /* Temporary variables for input, output */ + int32_t index; /* Index variables */ + q31_t wa, wb, wc, wd; /* Cubic interpolation coefficients */ + q31_t a, b, c, d; /* Four nearest output values */ + q31_t *tablePtr; /* Pointer to table */ + q31_t fract, fractCube, fractSquare; /* Temporary values for fractional values */ + q31_t oneBy6 = 0x15555555; /* Fixed point value of 1/6 */ + q31_t tableSpacing = TABLE_SPACING_Q31; /* Table spacing */ + q31_t temp; /* Temporary variable for intermediate process */ + + in = x; + + /* Calculate the nearest index */ + index = (uint32_t) in / (uint32_t) tableSpacing; + + /* Calculate the nearest value of input */ + in2 = (q31_t) index *tableSpacing; + + /* Calculation of fractional value */ + fract = (in - in2) << 8; + + /* fractSquare = fract * fract */ + fractSquare = ((q31_t) (((q63_t) fract * fract) >> 32)); + fractSquare = fractSquare << 1; + + /* fractCube = fract * fract * fract */ + fractCube = ((q31_t) (((q63_t) fractSquare * fract) >> 32)); + fractCube = fractCube << 1; + + /* Checking min and max index of table */ + if(index < 0) + { + index = 0; + } + else if(index > 256) + { + index = 256; + } + + /* Initialise table pointer */ + tablePtr = (q31_t *) & sinTableQ31[index]; + + /* Cubic interpolation process */ + /* Calculation of wa */ + /* wa = -(oneBy6)*fractCube + (fractSquare >> 1u) - (0x2AAAAAAA)*fract; */ + wa = ((q31_t) (((q63_t) oneBy6 * fractCube) >> 32)); + temp = 0x2AAAAAAA; + wa = (q31_t) ((((q63_t) wa << 32) + ((q63_t) temp * fract)) >> 32); + wa = -(wa << 1u); + wa += (fractSquare >> 1u); + + /* Read first nearest value of output from the sin table */ + a = *tablePtr++; + + /* sinVal = a*wa */ + sinVal = ((q31_t) (((q63_t) a * wa) >> 32)); + + /* q31(1.31) Fixed point value of 1 */ + temp = 0x7FFFFFFF; + + /* Calculation of wb */ + wb = ((fractCube >> 1u) - (fractSquare + (fract >> 1u))) + temp; + + /* Read second nearest value of output from the sin table */ + b = *tablePtr++; + + /* sinVal += b*wb */ + sinVal = (q31_t) ((((q63_t) sinVal << 32) + (q63_t) b * (wb)) >> 32); + + /* Calculation of wc */ + wc = -fractCube + fractSquare; + wc = (wc >> 1u) + fract; + + /* Read third nearest value of output from the sin table */ + c = *tablePtr++; + + /* sinVal += c*wc */ + sinVal = (q31_t) ((((q63_t) sinVal << 32) + ((q63_t) c * wc)) >> 32); + + /* Calculation of wd */ + /* wd = (oneBy6) * fractCube - (oneBy6) * fract; */ + fractCube = fractCube - fract; + wd = ((q31_t) (((q63_t) oneBy6 * fractCube) >> 32)); + wd = (wd << 1u); + + /* Read fourth nearest value of output from the sin table */ + d = *tablePtr++; + + /* sinVal += d*wd; */ + sinVal = (q31_t) ((((q63_t) sinVal << 32) + ((q63_t) d * wd)) >> 32); + + /* convert sinVal in 2.30 format to 1.31 format */ + return (__QADD(sinVal, sinVal)); + +} + +/** + * @} end of sin group + */