From 4447282260be0780eb6e36f5e953bf56888a5688 Mon Sep 17 00:00:00 2001 From: px4dev Date: Sun, 6 Jan 2013 12:52:05 -0800 Subject: Integrate the interesting parts of the CMSIS 3.01 (r3p1) DSP library --- .../Source/SupportFunctions/arm_q31_to_float.c | 123 +++++++++++++++++++++ 1 file changed, 123 insertions(+) create mode 100644 apps/mathlib/CMSIS/DSP_Lib/Source/SupportFunctions/arm_q31_to_float.c (limited to 'apps/mathlib/CMSIS/DSP_Lib/Source/SupportFunctions/arm_q31_to_float.c') diff --git a/apps/mathlib/CMSIS/DSP_Lib/Source/SupportFunctions/arm_q31_to_float.c b/apps/mathlib/CMSIS/DSP_Lib/Source/SupportFunctions/arm_q31_to_float.c new file mode 100644 index 000000000..94deec9a1 --- /dev/null +++ b/apps/mathlib/CMSIS/DSP_Lib/Source/SupportFunctions/arm_q31_to_float.c @@ -0,0 +1,123 @@ +/* ---------------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_q31_to_float.c +* +* Description: Converts the elements of the Q31 vector to floating-point vector. +* +* 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 groupSupport + */ + +/** + * @defgroup q31_to_x Convert 32-bit Integer value + */ + +/** + * @addtogroup q31_to_x + * @{ + */ + +/** + * @brief Converts the elements of the Q31 vector to floating-point vector. + * @param[in] *pSrc points to the Q31 input vector + * @param[out] *pDst points to the floating-point output vector + * @param[in] blockSize length of the input vector + * @return none. + * + * \par Description: + * + * The equation used for the conversion process is: + * + * 
    
+ * 	pDst[n] = (float32_t) pSrc[n] / 2147483648;   0 <= n < blockSize.    
+ *
+ * + */ + + +void arm_q31_to_float( + q31_t * pSrc, + float32_t * pDst, + uint32_t blockSize) +{ + q31_t *pIn = pSrc; /* Src pointer */ + uint32_t blkCnt; /* loop counter */ + + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + + /*loop Unrolling */ + blkCnt = blockSize >> 2u; + + /* 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) + { + /* C = (float32_t) A / 2147483648 */ + /* convert from q31 to float and then store the results in the destination buffer */ + *pDst++ = ((float32_t) * pIn++ / 2147483648.0f); + *pDst++ = ((float32_t) * pIn++ / 2147483648.0f); + *pDst++ = ((float32_t) * pIn++ / 2147483648.0f); + *pDst++ = ((float32_t) * pIn++ / 2147483648.0f); + + /* 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; + +#else + + /* Run the below code for Cortex-M0 */ + + /* Loop over blockSize number of values */ + blkCnt = blockSize; + +#endif /* #ifndef ARM_MATH_CM0 */ + + while(blkCnt > 0u) + { + /* C = (float32_t) A / 2147483648 */ + /* convert from q31 to float and then store the results in the destination buffer */ + *pDst++ = ((float32_t) * pIn++ / 2147483648.0f); + + /* Decrement the loop counter */ + blkCnt--; + } +} + +/** + * @} end of q31_to_x group + */ -- cgit v1.2.3