;* ======================================================================== *;
;* TEXAS INSTRUMENTS, INC. *;
;* *;
;* DSPLIB DSP Signal Processing Library *;
;* *;
;* Release: Version 1.02 *;
;* CVS Revision: 1.4 Sun Mar 10 00:53:44 2002 (UTC) *;
;* Snapshot date: 18-Apr-2002 *;
;* *;
;* This library contains proprietary intellectual property of Texas *;
;* Instruments, Inc. The library and its source code are protected by *;
;* various copyrights, and portions may also be protected by patents or *;
;* other legal protections. *;
;* *;
;* This software is licensed for use with Texas Instruments TMS320 *;
;* family DSPs. This license was provided to you prior to installing *;
;* the software. You may review this license by consulting the file *;
;* TI_license.PDF which accompanies the files in this library. *;
;* ------------------------------------------------------------------------ *;
;* Copyright (C) 2002 Texas Instruments, Incorporated. *;
;* All Rights Reserved. *;
;* ======================================================================== *;
* ========================================================================= *
* *
* TEXAS INSTRUMENTS, INC. *
* *
* NAME *
* DSP_firlms2 *
* *
* REVISION DATE *
* 06-Mar-2002 *
* *
* USAGE *
* This routine is C-callable and can be called as: *
* *
* long DSP_firlms2 *
* ( *
* short *restrict h, // Coefficient Array // *
* const short *restrict x, // Input Array // *
* short b, // Error of from previous FIR // *
* int nh // Number of coefficients // *
* ); *
* *
* DESCRIPTION *
* This is an Least Mean Squared Adaptive FIR Filter. Given the *
* error from the previous sample and pointer to the next sample *
* it computes an update of the coefficents and then performs *
* the FIR for the given input. Coefficents h[], input x[] and error *
* b are in Q.15 format. The output sample is returned as Q.30. *
* *
* long DSP_firlms2 *
* ( *
* short *restrict h, *
* const short *restrict x, *
* short b, *
* int nh *
* ) *
* { *
* int i; *
* long r = 0; *
* *
* for (i = 0; i < nh; i++) *
* { *
* h[i] += (x[i ] * b) >> 15; *
* r += x[i + 1] * h[i]; *
* } *
* *
* return r; *
* } *
* *
* *
* TECHNIQUES *
* The loop is unrolled once. *
* *
* ASSUMPTIONS *
* The number of coefficients nh must be a multiple of 2. *
* *
* MEMORY NOTE *
* This routine has no memory hits. *
* *
* NOTES *
* This routine is interupt-tolerant but not interruptible. *
* This code is ENDIAN NEUTRAL. *
* *
* CYCLES *
* 3 * nh/2 + 26 *
* For nh = 24: 62 cycles *
* For nh = 16: 50 cycles *
* *
* CODESIZE *
* 256 bytes. *
* *
* ------------------------------------------------------------------------- *
* Copyright (c) 2002 Texas Instruments, Incorporated. *
* All Rights Reserved. *
* ========================================================================= *
.global _DSP_firlms2
* ========================================================================= *
* End of file: dsp_firlms2.h62 *
* ------------------------------------------------------------------------- *
* Copyright (c) 2002 Texas Instruments, Incorporated. *
* All Rights Reserved. *
* ========================================================================= *