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authorAli Labbene <ali.labbene@st.com>2019-12-11 08:59:21 +0100
committerAli Labbene <ali.labbene@st.com>2019-12-16 16:35:24 +0100
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parent76177aa280494bb36d7a0bcbda1078d4db717020 (diff)
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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
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+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_sin_q15.c
+ * Description: Fast sine calculation for Q15 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 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)
+{
+ q15_t sinVal; /* Temporary variables for input, output */
+ int32_t index; /* Index variables */
+ q15_t a, b; /* Four nearest output values */
+ q15_t fract; /* Temporary values for fractional values */
+
+ /* Calculate the nearest index */
+ index = (uint32_t)x >> FAST_MATH_Q15_SHIFT;
+
+ /* Calculation of fractional value */
+ fract = (x - (index << FAST_MATH_Q15_SHIFT)) << 9;
+
+ /* Read two nearest values of input value from the sin table */
+ a = sinTable_q15[index];
+ b = sinTable_q15[index+1];
+
+ /* Linear interpolation process */
+ sinVal = (q31_t)(0x8000-fract)*a >> 16;
+ sinVal = (q15_t)((((q31_t)sinVal << 16) + ((q31_t)fract*b)) >> 16);
+
+ return sinVal << 1;
+}
+
+/**
+ * @} end of sin group
+ */