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diff --git a/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_q31.c b/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_q31.c
new file mode 100644
index 0000000..08e80fe
--- /dev/null
+++ b/cdc-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_q31.c
@@ -0,0 +1,169 @@
+/* ----------------------------------------------------------------------

+ * Project:      CMSIS DSP Library

+ * Title:        arm_var_q31.c

+ * Description:  Variance of an array of Q31 type

+ *

+ * $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"

+

+/**

+ * @ingroup groupStats

+ */

+

+/**

+ * @addtogroup variance

+ * @{

+ */

+

+/**

+ * @brief Variance of the elements of a Q31 vector.

+ * @param[in]       *pSrc points to the input vector

+ * @param[in]       blockSize length of the input vector

+ * @param[out]      *pResult variance value returned here

+ * @return none.

+ * @details

+ * <b>Scaling and Overflow Behavior:</b>

+ *

+ *\par

+ * The function is implemented using an internal 64-bit accumulator.

+ * The input is represented in 1.31 format, which is then downshifted by 8 bits

+ * which yields 1.23, and intermediate multiplication yields a 2.46 format.

+ * The accumulator maintains full precision of the intermediate multiplication results,

+ * but provides only a 16 guard bits.

+ * There is no saturation on intermediate additions.

+ * If the accumulator overflows it wraps around and distorts the result.

+ * In order to avoid overflows completely the input signal must be scaled down by

+ * log2(blockSize)-8 bits, as a total of blockSize additions are performed internally.

+ * After division, internal variables should be Q18.46

+ * Finally, the 18.46 accumulator is right shifted by 15 bits to yield a 1.31 format value.

+ *

+ */

+

+void arm_var_q31(

+  q31_t * pSrc,

+  uint32_t blockSize,

+  q31_t * pResult)

+{

+  q63_t sum = 0;                                 /* Accumulator */

+  q63_t meanOfSquares, squareOfMean;             /* square of mean and mean of square */

+  q31_t in;                                      /* input value */

+  uint32_t blkCnt;                               /* loop counter */

+  q63_t sumOfSquares = 0;                        /* Accumulator */

+

+  if (blockSize == 1U)

+  {

+    *pResult = 0;

+    return;

+  }

+

+#if defined (ARM_MATH_DSP)

+  /* 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 = (A[0] * A[0] + A[1] * A[1] + ... + A[blockSize-1] * A[blockSize-1])  */

+    /* Compute Sum of squares of the input samples

+     * and then store the result in a temporary variable, sum. */

+    in = *pSrc++ >> 8U;

+    sum += in;

+    sumOfSquares += ((q63_t) (in) * (in));

+    in = *pSrc++ >> 8U;

+    sum += in;

+    sumOfSquares += ((q63_t) (in) * (in));

+    in = *pSrc++ >> 8U;

+    sum += in;

+    sumOfSquares += ((q63_t) (in) * (in));

+    in = *pSrc++ >> 8U;

+    sum += in;

+    sumOfSquares += ((q63_t) (in) * (in));

+

+    /* 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;

+

+  while (blkCnt > 0U)

+  {

+    /* C = (A[0] * A[0] + A[1] * A[1] + ... + A[blockSize-1] * A[blockSize-1]) */

+    /* Compute Sum of squares of the input samples

+     * and then store the result in a temporary variable, sum. */

+    in = *pSrc++ >> 8U;

+    sum += in;

+    sumOfSquares += ((q63_t) (in) * (in));

+

+    /* Decrement the loop counter */

+    blkCnt--;

+  }

+

+  /* Compute Mean of squares of the input samples

+   * and then store the result in a temporary variable, meanOfSquares. */

+  meanOfSquares = sumOfSquares / (q63_t)(blockSize - 1U);

+

+#else

+  /* Run the below code for Cortex-M0 */

+

+  /* Loop over blockSize number of values */

+  blkCnt = blockSize;

+

+  while (blkCnt > 0U)

+  {

+    /* C = (A[0] * A[0] + A[1] * A[1] + ... + A[blockSize-1] * A[blockSize-1]) */

+    /* Compute Sum of squares of the input samples

+     * and then store the result in a temporary variable, sumOfSquares. */

+    in = *pSrc++ >> 8U;

+    sumOfSquares += ((q63_t) (in) * (in));

+

+    /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */

+    /* Compute sum of all input values and then store the result in a temporary variable, sum. */

+    sum += in;

+

+    /* Decrement the loop counter */

+    blkCnt--;

+  }

+

+  /* Compute Mean of squares of the input samples

+   * and then store the result in a temporary variable, meanOfSquares. */

+  meanOfSquares = sumOfSquares / (q63_t)(blockSize - 1U);

+

+#endif /* #if defined (ARM_MATH_DSP) */

+

+  /* Compute square of mean */

+  squareOfMean = sum * sum / (q63_t)(blockSize * (blockSize - 1U));

+

+  /* Compute standard deviation and then store the result to the destination */

+  *pResult = (meanOfSquares - squareOfMean) >> 15U;

+}

+

+/**

+ * @} end of variance group

+ */