arm_fir_q15.c
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00001 /* ---------------------------------------------------------------------- 00002 * Copyright (C) 2011 ARM Limited. All rights reserved. 00003 * 00004 * $Date: 15. December 2011 00005 * $Revision: V2.0.0 00006 * 00007 * Project: Cortex-R DSP Library 00008 * Title: arm_fir_q15.c 00009 * 00010 * Description: Q15 FIR filter processing function. 00011 * 00012 * Target Processor: Cortex-R4/R5 00013 * 00014 * Version 1.0.0 2011/03/08 00015 * Alpha release. 00016 * 00017 * Version 1.0.1 2011/09/30 00018 * Beta release. 00019 * 00020 * Version 2.0.0 2011/12/15 00021 * Final release. 00022 * 00023 * -------------------------------------------------------------------- */ 00024 00025 #include "arm_math.h" 00026 00064 #ifndef UNALIGNED_SUPPORT_DISABLE 00065 00066 void arm_fir_q15( 00067 const arm_fir_instance_q15 * S, 00068 q15_t * pSrc, 00069 q15_t * pDst, 00070 uint32_t blockSize) 00071 { 00072 q15_t *pState = S->pState; /* State pointer */ 00073 q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */ 00074 q15_t *pStateCurnt; /* Points to the current sample of the state */ 00075 q15_t *px1; /* Temporary q15 pointer for state buffer */ 00076 q15_t *pb; /* Temporary pointer for coefficient buffer */ 00077 q31_t x0, x1, x2, x3, c0; /* Temporary variables to hold SIMD state and coefficient values */ 00078 q63_t acc0, acc1, acc2, acc3; /* Accumulators */ 00079 uint32_t numTaps = S->numTaps; /* Number of taps in the filter */ 00080 uint32_t tapCnt, blkCnt; /* Loop counters */ 00081 00082 00083 /* S->pState points to state array which contains previous frame (numTaps - 1) samples */ 00084 /* pStateCurnt points to the location where the new input data should be written */ 00085 pStateCurnt = &(S->pState[(numTaps - 1u)]); 00086 00087 /* Apply loop unrolling and compute 4 output values simultaneously. 00088 * The variables acc0 ... acc3 hold output values that are being computed: 00089 * 00090 * acc0 = b[numTaps-1] * x[n-numTaps-1] + b[numTaps-2] * x[n-numTaps-2] + b[numTaps-3] * x[n-numTaps-3] +...+ b[0] * x[0] 00091 * acc1 = b[numTaps-1] * x[n-numTaps] + b[numTaps-2] * x[n-numTaps-1] + b[numTaps-3] * x[n-numTaps-2] +...+ b[0] * x[1] 00092 * acc2 = b[numTaps-1] * x[n-numTaps+1] + b[numTaps-2] * x[n-numTaps] + b[numTaps-3] * x[n-numTaps-1] +...+ b[0] * x[2] 00093 * acc3 = b[numTaps-1] * x[n-numTaps+2] + b[numTaps-2] * x[n-numTaps+1] + b[numTaps-3] * x[n-numTaps] +...+ b[0] * x[3] 00094 */ 00095 00096 blkCnt = blockSize >> 2; 00097 00098 /* First part of the processing with loop unrolling. Compute 4 outputs at a time. 00099 ** a second loop below computes the remaining 1 to 3 samples. */ 00100 while(blkCnt > 0u) 00101 { 00102 /* Copy four new input samples into the state buffer. 00103 ** Use 32-bit SIMD to move the 16-bit data. Only requires two copies. */ 00104 *__SIMD32(pStateCurnt)++ = *__SIMD32(pSrc)++; 00105 *__SIMD32(pStateCurnt)++ = *__SIMD32(pSrc)++; 00106 00107 /* Set all accumulators to zero */ 00108 acc0 = 0; 00109 acc1 = 0; 00110 acc2 = 0; 00111 acc3 = 0; 00112 00113 /* Initialize state pointer of type q15 */ 00114 px1 = pState; 00115 00116 /* Initialize coeff pointer of type q31 */ 00117 pb = pCoeffs; 00118 00119 /* Read the first two samples from the state buffer: x[n-N], x[n-N-1] */ 00120 x0 = _SIMD32_OFFSET(px1); 00121 00122 /* Read the third and forth samples from the state buffer: x[n-N-1], x[n-N-2] */ 00123 x1 = _SIMD32_OFFSET(px1 + 1u); 00124 00125 px1 += 2u; 00126 00127 /* Loop over the number of taps. Unroll by a factor of 4. 00128 ** Repeat until we've computed numTaps-4 coefficients. */ 00129 tapCnt = numTaps >> 2; 00130 00131 while(tapCnt > 0u) 00132 { 00133 /* Read the first two coefficients using SIMD: b[N] and b[N-1] coefficients */ 00134 c0 = *__SIMD32(pb)++; 00135 00136 /* acc0 += b[N] * x[n-N] + b[N-1] * x[n-N-1] */ 00137 acc0 = __SMLALD(x0, c0, acc0); 00138 00139 /* acc1 += b[N] * x[n-N-1] + b[N-1] * x[n-N-2] */ 00140 acc1 = __SMLALD(x1, c0, acc1); 00141 00142 /* Read state x[n-N-2], x[n-N-3] */ 00143 x2 = _SIMD32_OFFSET(px1); 00144 00145 /* Read state x[n-N-3], x[n-N-4] */ 00146 x3 = _SIMD32_OFFSET(px1 + 1u); 00147 00148 /* acc2 += b[N] * x[n-N-2] + b[N-1] * x[n-N-3] */ 00149 acc2 = __SMLALD(x2, c0, acc2); 00150 00151 /* acc3 += b[N] * x[n-N-3] + b[N-1] * x[n-N-4] */ 00152 acc3 = __SMLALD(x3, c0, acc3); 00153 00154 /* Read coefficients b[N-2], b[N-3] */ 00155 c0 = *__SIMD32(pb)++; 00156 00157 /* acc0 += b[N-2] * x[n-N-2] + b[N-3] * x[n-N-3] */ 00158 acc0 = __SMLALD(x2, c0, acc0); 00159 00160 /* acc1 += b[N-2] * x[n-N-3] + b[N-3] * x[n-N-4] */ 00161 acc1 = __SMLALD(x3, c0, acc1); 00162 00163 /* Read state x[n-N-4], x[n-N-5] */ 00164 x0 = _SIMD32_OFFSET(px1 + 2u); 00165 00166 /* Read state x[n-N-5], x[n-N-6] */ 00167 x1 = _SIMD32_OFFSET(px1 + 3u); 00168 00169 /* acc2 += b[N-2] * x[n-N-4] + b[N-3] * x[n-N-5] */ 00170 acc2 = __SMLALD(x0, c0, acc2); 00171 00172 /* acc3 += b[N-2] * x[n-N-5] + b[N-3] * x[n-N-6] */ 00173 acc3 = __SMLALD(x1, c0, acc3); 00174 00175 px1 += 4u; 00176 00177 tapCnt--; 00178 00179 } 00180 00181 00182 /* If the filter length is not a multiple of 4, compute the remaining filter taps. 00183 ** This is always be 2 taps since the filter length is even. */ 00184 if((numTaps & 0x3u) != 0u) 00185 { 00186 /* Read 2 coefficients */ 00187 c0 = *__SIMD32(pb)++; 00188 00189 /* Fetch 4 state variables */ 00190 x2 = _SIMD32_OFFSET(px1); 00191 00192 x3 = _SIMD32_OFFSET(px1 + 1u); 00193 00194 /* Perform the multiply-accumulates */ 00195 acc0 = __SMLALD(x0, c0, acc0); 00196 00197 px1 += 2u; 00198 00199 acc1 = __SMLALD(x1, c0, acc1); 00200 acc2 = __SMLALD(x2, c0, acc2); 00201 acc3 = __SMLALD(x3, c0, acc3); 00202 } 00203 00204 /* The results in the 4 accumulators are in 2.30 format. Convert to 1.15 with saturation. 00205 ** Then store the 4 outputs in the destination buffer. */ 00206 00207 #ifndef ARM_MATH_BIG_ENDIAN 00208 00209 *__SIMD32(pDst)++ = 00210 #ifdef CCS 00211 __PKHBT(__SSATA(acc0, 15, 16), __SSATA(acc1, 15, 16), 16); 00212 *__SIMD32(pDst)++ = 00213 __PKHBT(__SSATA(acc2, 15, 16), __SSATA(acc3, 15, 16), 16); 00214 #else 00215 __PKHBT(__SSAT((acc0 >> 15), 16), __SSAT((acc1 >> 15), 16), 16); 00216 *__SIMD32(pDst)++ = 00217 __PKHBT(__SSAT((acc2 >> 15), 16), __SSAT((acc3 >> 15), 16), 16); 00218 #endif 00219 00220 #else 00221 00222 *__SIMD32(pDst)++ = 00223 #ifdef CCS 00224 __PKHBT(__SSATA(acc1, 15, 16), __SSATA(acc0, 15, 16), 16); 00225 *__SIMD32(pDst)++ = 00226 __PKHBT(__SSATA(acc3, 15, 16), __SSATA(acc2, 15, 16), 16); 00227 #else 00228 00229 __PKHBT(__SSAT((acc1 >> 15), 16), __SSAT((acc0 >> 15), 16), 16); 00230 *__SIMD32(pDst)++ = 00231 __PKHBT(__SSAT((acc3 >> 15), 16), __SSAT((acc2 >> 15), 16), 16); 00232 00233 #endif 00234 00235 #endif /* #ifndef ARM_MATH_BIG_ENDIAN */ 00236 00237 00238 /* Advance the state pointer by 4 to process the next group of 4 samples */ 00239 pState = pState + 4; 00240 00241 /* Decrement the loop counter */ 00242 blkCnt--; 00243 } 00244 00245 /* If the blockSize is not a multiple of 4, compute any remaining output samples here. 00246 ** No loop unrolling is used. */ 00247 blkCnt = blockSize % 0x4u; 00248 while(blkCnt > 0u) 00249 { 00250 /* Copy two samples into state buffer */ 00251 *pStateCurnt++ = *pSrc++; 00252 00253 /* Set the accumulator to zero */ 00254 acc0 = 0; 00255 00256 /* Initialize state pointer of type q15 */ 00257 px1 = pState; 00258 00259 /* Initialize coeff pointer of type q31 */ 00260 pb = pCoeffs; 00261 00262 tapCnt = numTaps >> 1; 00263 00264 do 00265 { 00266 00267 c0 = *__SIMD32(pb)++; 00268 x0 = *__SIMD32(px1)++; 00269 00270 acc0 = __SMLALD(x0, c0, acc0); 00271 tapCnt--; 00272 } 00273 while(tapCnt > 0u); 00274 00275 /* The result is in 2.30 format. Convert to 1.15 with saturation. 00276 ** Then store the output in the destination buffer. */ 00277 #ifdef CCS 00278 *pDst++ = (q15_t) (__SSATA(acc0, 15, 16)); 00279 #else 00280 *pDst++ = (q15_t) (__SSAT((acc0 >> 15), 16)); 00281 00282 #endif 00283 /* Advance state pointer by 1 for the next sample */ 00284 pState = pState + 1; 00285 00286 /* Decrement the loop counter */ 00287 blkCnt--; 00288 } 00289 00290 /* Processing is complete. 00291 ** Now copy the last numTaps - 1 samples to the satrt of the state buffer. 00292 ** This prepares the state buffer for the next function call. */ 00293 00294 /* Points to the start of the state buffer */ 00295 pStateCurnt = S->pState; 00296 00297 /* Calculation of count for copying integer writes */ 00298 tapCnt = (numTaps - 1u) >> 3; 00299 00300 while(tapCnt > 0u) 00301 { 00302 00303 /* Copy state values to start of state buffer */ 00304 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++; 00305 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++; 00306 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++; 00307 *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++; 00308 00309 tapCnt--; 00310 00311 } 00312 00313 /* Calculation of count for remaining q15_t data */ 00314 tapCnt = (numTaps - 1u) % 8u; 00315 00316 /* copy remaining data */ 00317 while(tapCnt > 0u) 00318 { 00319 *pStateCurnt++ = *pState++; 00320 00321 /* Decrement the loop counter */ 00322 tapCnt--; 00323 } 00324 } 00325 00326 #else 00327 00328 00329 void arm_fir_q15( 00330 const arm_fir_instance_q15 * S, 00331 q15_t * pSrc, 00332 q15_t * pDst, 00333 uint32_t blockSize) 00334 { 00335 q15_t *pState = S->pState; /* State pointer */ 00336 q15_t *pCoeffs = S->pCoeffs; /* Coefficient pointer */ 00337 q15_t *pStateCurnt; /* Points to the current sample of the state */ 00338 q63_t acc0, acc1, acc2, acc3; /* Accumulators */ 00339 q15_t *pb; /* Temporary pointer for coefficient buffer */ 00340 q15_t *px; /* Temporary q31 pointer for SIMD state buffer accesses */ 00341 q31_t x0, x1, x2, c0; /* Temporary variables to hold SIMD state and coefficient values */ 00342 uint32_t numTaps = S->numTaps; /* Number of taps in the filter */ 00343 uint32_t tapCnt, blkCnt; /* Loop counters */ 00344 00345 00346 /* S->pState points to state array which contains previous frame (numTaps - 1) samples */ 00347 /* pStateCurnt points to the location where the new input data should be written */ 00348 pStateCurnt = &(S->pState[(numTaps - 1u)]); 00349 00350 /* Apply loop unrolling and compute 4 output values simultaneously. 00351 * The variables acc0 ... acc3 hold output values that are being computed: 00352 * 00353 * acc0 = b[numTaps-1] * x[n-numTaps-1] + b[numTaps-2] * x[n-numTaps-2] + b[numTaps-3] * x[n-numTaps-3] +...+ b[0] * x[0] 00354 * acc1 = b[numTaps-1] * x[n-numTaps] + b[numTaps-2] * x[n-numTaps-1] + b[numTaps-3] * x[n-numTaps-2] +...+ b[0] * x[1] 00355 * acc2 = b[numTaps-1] * x[n-numTaps+1] + b[numTaps-2] * x[n-numTaps] + b[numTaps-3] * x[n-numTaps-1] +...+ b[0] * x[2] 00356 * acc3 = b[numTaps-1] * x[n-numTaps+2] + b[numTaps-2] * x[n-numTaps+1] + b[numTaps-3] * x[n-numTaps] +...+ b[0] * x[3] 00357 */ 00358 00359 blkCnt = blockSize >> 2; 00360 00361 /* First part of the processing with loop unrolling. Compute 4 outputs at a time. 00362 ** a second loop below computes the remaining 1 to 3 samples. */ 00363 while(blkCnt > 0u) 00364 { 00365 /* Copy four new input samples into the state buffer. 00366 ** Use 32-bit SIMD to move the 16-bit data. Only requires two copies. */ 00367 *pStateCurnt++ = *pSrc++; 00368 *pStateCurnt++ = *pSrc++; 00369 *pStateCurnt++ = *pSrc++; 00370 *pStateCurnt++ = *pSrc++; 00371 00372 00373 /* Set all accumulators to zero */ 00374 acc0 = 0; 00375 acc1 = 0; 00376 acc2 = 0; 00377 acc3 = 0; 00378 00379 /* Typecast q15_t pointer to q31_t pointer for state reading in q31_t */ 00380 px = pState; 00381 00382 /* Typecast q15_t pointer to q31_t pointer for coefficient reading in q31_t */ 00383 pb = pCoeffs; 00384 00385 /* Read the first two samples from the state buffer: x[n-N], x[n-N-1] */ 00386 x0 = *__SIMD32(px)++; 00387 00388 /* Read the third and forth samples from the state buffer: x[n-N-2], x[n-N-3] */ 00389 x2 = *__SIMD32(px)++; 00390 00391 /* Loop over the number of taps. Unroll by a factor of 4. 00392 ** Repeat until we've computed numTaps-(numTaps%4) coefficients. */ 00393 tapCnt = numTaps >> 2; 00394 00395 while(tapCnt > 0) 00396 { 00397 /* Read the first two coefficients using SIMD: b[N] and b[N-1] coefficients */ 00398 c0 = *__SIMD32(pb)++; 00399 00400 /* acc0 += b[N] * x[n-N] + b[N-1] * x[n-N-1] */ 00401 acc0 = __SMLALD(x0, c0, acc0); 00402 00403 /* acc2 += b[N] * x[n-N-2] + b[N-1] * x[n-N-3] */ 00404 acc2 = __SMLALD(x2, c0, acc2); 00405 00406 /* pack x[n-N-1] and x[n-N-2] */ 00407 #ifndef ARM_MATH_BIG_ENDIAN 00408 x1 = __PKHBT(x2, x0, 0); 00409 #else 00410 x1 = __PKHBT(x0, x2, 0); 00411 #endif 00412 00413 /* Read state x[n-N-4], x[n-N-5] */ 00414 x0 = _SIMD32_OFFSET(px); 00415 00416 /* acc1 += b[N] * x[n-N-1] + b[N-1] * x[n-N-2] */ 00417 acc1 = __SMLALDX(x1, c0, acc1); 00418 00419 /* pack x[n-N-3] and x[n-N-4] */ 00420 #ifndef ARM_MATH_BIG_ENDIAN 00421 x1 = __PKHBT(x0, x2, 0); 00422 #else 00423 x1 = __PKHBT(x2, x0, 0); 00424 #endif 00425 00426 /* acc3 += b[N] * x[n-N-3] + b[N-1] * x[n-N-4] */ 00427 acc3 = __SMLALDX(x1, c0, acc3); 00428 00429 /* Read coefficients b[N-2], b[N-3] */ 00430 c0 = *__SIMD32(pb)++; 00431 00432 /* acc0 += b[N-2] * x[n-N-2] + b[N-3] * x[n-N-3] */ 00433 acc0 = __SMLALD(x2, c0, acc0); 00434 00435 /* Read state x[n-N-6], x[n-N-7] with offset */ 00436 x2 = _SIMD32_OFFSET(px + 2u); 00437 00438 /* acc2 += b[N-2] * x[n-N-4] + b[N-3] * x[n-N-5] */ 00439 acc2 = __SMLALD(x0, c0, acc2); 00440 00441 /* acc1 += b[N-2] * x[n-N-3] + b[N-3] * x[n-N-4] */ 00442 acc1 = __SMLALDX(x1, c0, acc1); 00443 00444 /* pack x[n-N-5] and x[n-N-6] */ 00445 #ifndef ARM_MATH_BIG_ENDIAN 00446 x1 = __PKHBT(x2, x0, 0); 00447 #else 00448 x1 = __PKHBT(x0, x2, 0); 00449 #endif 00450 00451 /* acc3 += b[N-2] * x[n-N-5] + b[N-3] * x[n-N-6] */ 00452 acc3 = __SMLALDX(x1, c0, acc3); 00453 00454 /* Update state pointer for next state reading */ 00455 px += 4u; 00456 00457 /* Decrement tap count */ 00458 tapCnt--; 00459 00460 } 00461 00462 /* If the filter length is not a multiple of 4, compute the remaining filter taps. 00463 ** This is always be 2 taps since the filter length is even. */ 00464 if((numTaps & 0x3u) != 0u) 00465 { 00466 00467 /* Read last two coefficients */ 00468 c0 = *__SIMD32(pb)++; 00469 00470 /* Perform the multiply-accumulates */ 00471 acc0 = __SMLALD(x0, c0, acc0); 00472 acc2 = __SMLALD(x2, c0, acc2); 00473 00474 /* pack state variables */ 00475 #ifndef ARM_MATH_BIG_ENDIAN 00476 x1 = __PKHBT(x2, x0, 0); 00477 #else 00478 x1 = __PKHBT(x0, x2, 0); 00479 #endif 00480 00481 /* Read last state variables */ 00482 x0 = *__SIMD32(px); 00483 00484 /* Perform the multiply-accumulates */ 00485 acc1 = __SMLALDX(x1, c0, acc1); 00486 00487 /* pack state variables */ 00488 #ifndef ARM_MATH_BIG_ENDIAN 00489 x1 = __PKHBT(x0, x2, 0); 00490 #else 00491 x1 = __PKHBT(x2, x0, 0); 00492 #endif 00493 00494 /* Perform the multiply-accumulates */ 00495 acc3 = __SMLALDX(x1, c0, acc3); 00496 } 00497 00498 /* The results in the 4 accumulators are in 2.30 format. Convert to 1.15 with saturation. 00499 ** Then store the 4 outputs in the destination buffer. */ 00500 00501 #ifndef ARM_MATH_BIG_ENDIAN 00502 00503 *__SIMD32(pDst)++ = 00504 #ifdef CCS 00505 __PKHBT(__SSATA(acc0, 15, 16), __SSATA(acc1, 15, 16), 16); 00506 00507 *__SIMD32(pDst)++ = 00508 __PKHBT(__SSATA(acc2, 15, 16), __SSATA(acc3, 15, 16), 16); 00509 #else 00510 __PKHBT(__SSAT((acc0 >> 15), 16), __SSAT((acc1 >> 15), 16), 16); 00511 00512 *__SIMD32(pDst)++ = 00513 __PKHBT(__SSAT((acc2 >> 15), 16), __SSAT((acc3 >> 15), 16), 16); 00514 #endif 00515 00516 #else 00517 00518 *__SIMD32(pDst)++ = 00519 #ifdef CCS 00520 __PKHBT(__SSATA(acc1, 15, 16), __SSATA(acc0, 15, 16), 16); 00521 00522 *__SIMD32(pDst)++ = 00523 __PKHBT(__SSATA(acc3, 15, 16), __SSATA(acc2, 15, 16), 16); 00524 #else 00525 __PKHBT(__SSAT((acc1 >> 15), 16), __SSAT((acc0 >> 15), 16), 16); 00526 00527 *__SIMD32(pDst)++ = 00528 __PKHBT(__SSAT((acc3 >> 15), 16), __SSAT((acc2 >> 15), 16), 16); 00529 00530 #endif 00531 00532 #endif /* #ifndef ARM_MATH_BIG_ENDIAN */ 00533 00534 /* Advance the state pointer by 4 to process the next group of 4 samples */ 00535 pState = pState + 4; 00536 00537 /* Decrement the loop counter */ 00538 blkCnt--; 00539 } 00540 00541 /* If the blockSize is not a multiple of 4, compute any remaining output samples here. 00542 ** No loop unrolling is used. */ 00543 blkCnt = blockSize % 0x4u; 00544 while(blkCnt > 0u) 00545 { 00546 /* Copy two samples into state buffer */ 00547 *pStateCurnt++ = *pSrc++; 00548 00549 /* Set the accumulator to zero */ 00550 acc0 = 0; 00551 00552 /* Use SIMD to hold states and coefficients */ 00553 px = pState; 00554 pb = pCoeffs; 00555 00556 tapCnt = numTaps >> 1u; 00557 00558 do 00559 { 00560 x0 = *__SIMD32(px)++; 00561 c0 = *__SIMD32(pb)++; 00562 00563 acc0 = __SMLALD(x0, c0, acc0); 00564 tapCnt--; 00565 } 00566 while(tapCnt > 0u); 00567 00568 /* The result is in 2.30 format. Convert to 1.15 with saturation. 00569 ** Then store the output in the destination buffer. */ 00570 #ifdef CCS 00571 *pDst++ = (q15_t) (__SSATA(acc0, 15, 16)); 00572 #else 00573 *pDst++ = (q15_t) (__SSAT((acc0 >> 15), 16)); 00574 #endif 00575 00576 /* Advance state pointer by 1 for the next sample */ 00577 pState = pState + 1u; 00578 00579 /* Decrement the loop counter */ 00580 blkCnt--; 00581 } 00582 00583 /* Processing is complete. 00584 ** Now copy the last numTaps - 1 samples to the satrt of the state buffer. 00585 ** This prepares the state buffer for the next function call. */ 00586 00587 /* Points to the start of the state buffer */ 00588 pStateCurnt = S->pState; 00589 00590 /* Calculation of count for copying integer writes */ 00591 tapCnt = (numTaps - 1u) >> 2; 00592 00593 while(tapCnt > 0u) 00594 { 00595 *pStateCurnt++ = *pState++; 00596 *pStateCurnt++ = *pState++; 00597 *pStateCurnt++ = *pState++; 00598 *pStateCurnt++ = *pState++; 00599 00600 tapCnt--; 00601 00602 } 00603 00604 /* Calculation of count for remaining q15_t data */ 00605 tapCnt = (numTaps - 1u) % 0x4u; 00606 00607 /* copy remaining data */ 00608 while(tapCnt > 0u) 00609 { 00610 *pStateCurnt++ = *pState++; 00611 00612 /* Decrement the loop counter */ 00613 tapCnt--; 00614 } 00615 } 00616 00617 00618 #endif 00619 00620 00621
