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author | Ali Labbene <ali.labbene@st.com> | 2019-12-11 08:59:21 +0100 |
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committer | Ali Labbene <ali.labbene@st.com> | 2019-12-16 16:35:24 +0100 |
commit | 9f95ff5b6ba01db09552b84a0ab79607060a2666 (patch) | |
tree | 8a6e0dda832555c692307869aed49d07ee7facfe /DSP/Source/FastMathFunctions/arm_sin_q31.c | |
parent | 76177aa280494bb36d7a0bcbda1078d4db717020 (diff) | |
download | st-cmsis-core-lowfat-9f95ff5b6ba01db09552b84a0ab79607060a2666.tar.gz st-cmsis-core-lowfat-9f95ff5b6ba01db09552b84a0ab79607060a2666.tar.bz2 st-cmsis-core-lowfat-9f95ff5b6ba01db09552b84a0ab79607060a2666.zip |
Official ARM version: v5.4.0
Add CMSIS V5.4.0, please refer to index.html available under \docs folder.
Note: content of \CMSIS\Core\Include has been copied under \Include to keep the same structure
used in existing projects, and thus avoid projects mass update
Note: the following components have been removed from ARM original delivery (as not used in ST packages)
- CMSIS_EW2018.pdf
- .gitattributes
- .gitignore
- \Device
- \CMSIS
- \CoreValidation
- \DAP
- \Documentation
- \DoxyGen
- \Driver
- \Pack
- \RTOS\CMSIS_RTOS_Tutorial.pdf
- \RTOS\RTX
- \RTOS\Template
- \RTOS2\RTX
- \Utilities
- All ARM/GCC projects files are deleted from \DSP, \RTOS and \RTOS2
Change-Id: Ia026c3f0f0d016627a4fb5a9032852c33d24b4d3
Diffstat (limited to 'DSP/Source/FastMathFunctions/arm_sin_q31.c')
-rw-r--r-- | DSP/Source/FastMathFunctions/arm_sin_q31.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/DSP/Source/FastMathFunctions/arm_sin_q31.c b/DSP/Source/FastMathFunctions/arm_sin_q31.c new file mode 100644 index 0000000..8d3c7ac --- /dev/null +++ b/DSP/Source/FastMathFunctions/arm_sin_q31.c @@ -0,0 +1,75 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_sin_q31.c + * Description: Fast sine calculation for Q31 values + * + * $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" +#include "arm_common_tables.h" + +/** + * @ingroup groupFastMath + */ + + /** + * @addtogroup sin + * @{ + */ + +/** + * @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). */ + +q31_t arm_sin_q31( + q31_t x) +{ + q31_t sinVal; /* Temporary variables for input, output */ + int32_t index; /* Index variables */ + q31_t a, b; /* Four nearest output values */ + q31_t fract; /* Temporary values for fractional values */ + + /* Calculate the nearest index */ + index = (uint32_t)x >> FAST_MATH_Q31_SHIFT; + + /* Calculation of fractional value */ + fract = (x - (index << FAST_MATH_Q31_SHIFT)) << 9; + + /* Read two nearest values of input value from the sin table */ + a = sinTable_q31[index]; + b = sinTable_q31[index+1]; + + /* Linear interpolation process */ + sinVal = (q63_t)(0x80000000-fract)*a >> 32; + sinVal = (q31_t)((((q63_t)sinVal << 32) + ((q63_t)fract*b)) >> 32); + + return sinVal << 1; +} + +/** + * @} end of sin group + */ |