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diff --git a/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_lms_q15.c b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_lms_q15.c
new file mode 100644
index 0000000..8d5226e
--- /dev/null
+++ b/fw/midi-dials/Drivers/CMSIS/DSP/Source/FilteringFunctions/arm_lms_q15.c
@@ -0,0 +1,368 @@
+/* ----------------------------------------------------------------------
+ * Project:      CMSIS DSP Library
+ * Title:        arm_lms_q15.c
+ * Description:  Processing function for the Q15 LMS filter
+ *
+ * $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 groupFilters
+ */
+
+/**
+ * @addtogroup LMS
+ * @{
+ */
+
+ /**
+ * @brief Processing function for Q15 LMS filter.
+ * @param[in] *S points to an instance of the Q15 LMS filter structure.
+ * @param[in] *pSrc points to the block of input data.
+ * @param[in] *pRef points to the block of reference data.
+ * @param[out] *pOut points to the block of output data.
+ * @param[out] *pErr points to the block of error data.
+ * @param[in] blockSize number of samples to process.
+ * @return none.
+ *
+ * \par Scaling and Overflow Behavior:
+ * The function is implemented using a 64-bit internal accumulator.
+ * Both coefficients and state variables are represented in 1.15 format and multiplications yield a 2.30 result.
+ * The 2.30 intermediate results are accumulated in a 64-bit accumulator in 34.30 format.
+ * There is no risk of internal overflow with this approach and the full precision of intermediate multiplications is preserved.
+ * After all additions have been performed, the accumulator is truncated to 34.15 format by discarding low 15 bits.
+ * Lastly, the accumulator is saturated to yield a result in 1.15 format.
+ *
+ * \par
+ * 	In this filter, filter coefficients are updated for each sample and the updation of filter cofficients are saturted.
+ *
+ */
+
+void arm_lms_q15(
+  const arm_lms_instance_q15 * S,
+  q15_t * pSrc,
+  q15_t * pRef,
+  q15_t * pOut,
+  q15_t * pErr,
+  uint32_t blockSize)
+{
+  q15_t *pState = S->pState;                     /* State pointer */
+  uint32_t numTaps = S->numTaps;                 /* Number of filter coefficients in the filter */
+  q15_t *pCoeffs = S->pCoeffs;                   /* Coefficient pointer */
+  q15_t *pStateCurnt;                            /* Points to the current sample of the state */
+  q15_t mu = S->mu;                              /* Adaptive factor */
+  q15_t *px;                                     /* Temporary pointer for state */
+  q15_t *pb;                                     /* Temporary pointer for coefficient buffer */
+  uint32_t tapCnt, blkCnt;                       /* Loop counters */
+  q63_t acc;                                     /* Accumulator */
+  q15_t e = 0;                                   /* error of data sample */
+  q15_t alpha;                                   /* Intermediate constant for taps update */
+  q31_t coef;                                    /* Teporary variable for coefficient */
+  q31_t acc_l, acc_h;
+  int32_t lShift = (15 - (int32_t) S->postShift);       /*  Post shift  */
+  int32_t uShift = (32 - lShift);
+
+
+#if defined (ARM_MATH_DSP)
+
+  /* Run the below code for Cortex-M4 and Cortex-M3 */
+
+
+  /* S->pState points to buffer which contains previous frame (numTaps - 1) samples */
+  /* pStateCurnt points to the location where the new input data should be written */
+  pStateCurnt = &(S->pState[(numTaps - 1U)]);
+
+  /* Initializing blkCnt with blockSize */
+  blkCnt = blockSize;
+
+  while (blkCnt > 0U)
+  {
+    /* Copy the new input sample into the state buffer */
+    *pStateCurnt++ = *pSrc++;
+
+    /* Initialize state pointer */
+    px = pState;
+
+    /* Initialize coefficient pointer */
+    pb = pCoeffs;
+
+    /* Set the accumulator to zero */
+    acc = 0;
+
+    /* Loop unrolling.  Process 4 taps at a time. */
+    tapCnt = numTaps >> 2U;
+
+    while (tapCnt > 0U)
+    {
+      /* acc +=  b[N] * x[n-N] + b[N-1] * x[n-N-1] */
+      /* Perform the multiply-accumulate */
+#ifndef UNALIGNED_SUPPORT_DISABLE
+
+      acc = __SMLALD(*__SIMD32(px)++, (*__SIMD32(pb)++), acc);
+      acc = __SMLALD(*__SIMD32(px)++, (*__SIMD32(pb)++), acc);
+
+#else
+
+      acc += (q63_t) (((q31_t) (*px++) * (*pb++)));
+      acc += (q63_t) (((q31_t) (*px++) * (*pb++)));
+      acc += (q63_t) (((q31_t) (*px++) * (*pb++)));
+      acc += (q63_t) (((q31_t) (*px++) * (*pb++)));
+
+
+#endif	/*	#ifndef UNALIGNED_SUPPORT_DISABLE	*/
+
+      /* Decrement the loop counter */
+      tapCnt--;
+    }
+
+    /* If the filter length is not a multiple of 4, compute the remaining filter taps */
+    tapCnt = numTaps % 0x4U;
+
+    while (tapCnt > 0U)
+    {
+      /* Perform the multiply-accumulate */
+      acc += (q63_t) (((q31_t) (*px++) * (*pb++)));
+
+      /* Decrement the loop counter */
+      tapCnt--;
+    }
+
+    /* Calc lower part of acc */
+    acc_l = acc & 0xffffffff;
+
+    /* Calc upper part of acc */
+    acc_h = (acc >> 32) & 0xffffffff;
+
+    /* Apply shift for lower part of acc and upper part of acc */
+    acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
+
+    /* Converting the result to 1.15 format and saturate the output */
+    acc = __SSAT(acc, 16);
+
+    /* Store the result from accumulator into the destination buffer. */
+    *pOut++ = (q15_t) acc;
+
+    /* Compute and store error */
+    e = *pRef++ - (q15_t) acc;
+
+    *pErr++ = (q15_t) e;
+
+    /* Compute alpha i.e. intermediate constant for taps update */
+    alpha = (q15_t) (((q31_t) e * (mu)) >> 15);
+
+    /* Initialize state pointer */
+    /* Advance state pointer by 1 for the next sample */
+    px = pState++;
+
+    /* Initialize coefficient pointer */
+    pb = pCoeffs;
+
+    /* Loop unrolling.  Process 4 taps at a time. */
+    tapCnt = numTaps >> 2U;
+
+    /* Update filter coefficients */
+    while (tapCnt > 0U)
+    {
+      coef = (q31_t) * pb + (((q31_t) alpha * (*px++)) >> 15);
+      *pb++ = (q15_t) __SSAT((coef), 16);
+      coef = (q31_t) * pb + (((q31_t) alpha * (*px++)) >> 15);
+      *pb++ = (q15_t) __SSAT((coef), 16);
+      coef = (q31_t) * pb + (((q31_t) alpha * (*px++)) >> 15);
+      *pb++ = (q15_t) __SSAT((coef), 16);
+      coef = (q31_t) * pb + (((q31_t) alpha * (*px++)) >> 15);
+      *pb++ = (q15_t) __SSAT((coef), 16);
+
+      /* Decrement the loop counter */
+      tapCnt--;
+    }
+
+    /* If the filter length is not a multiple of 4, compute the remaining filter taps */
+    tapCnt = numTaps % 0x4U;
+
+    while (tapCnt > 0U)
+    {
+      /* Perform the multiply-accumulate */
+      coef = (q31_t) * pb + (((q31_t) alpha * (*px++)) >> 15);
+      *pb++ = (q15_t) __SSAT((coef), 16);
+
+      /* Decrement the loop counter */
+      tapCnt--;
+    }
+
+    /* Decrement the loop counter */
+    blkCnt--;
+
+  }
+
+  /* Processing is complete. Now copy the last numTaps - 1 samples to the
+     satrt of the state buffer. This prepares the state buffer for the
+     next function call. */
+
+  /* Points to the start of the pState buffer */
+  pStateCurnt = S->pState;
+
+  /* Calculation of count for copying integer writes */
+  tapCnt = (numTaps - 1U) >> 2;
+
+  while (tapCnt > 0U)
+  {
+
+#ifndef UNALIGNED_SUPPORT_DISABLE
+
+    *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
+    *__SIMD32(pStateCurnt)++ = *__SIMD32(pState)++;
+#else
+    *pStateCurnt++ = *pState++;
+    *pStateCurnt++ = *pState++;
+    *pStateCurnt++ = *pState++;
+    *pStateCurnt++ = *pState++;
+#endif
+
+    tapCnt--;
+
+  }
+
+  /* Calculation of count for remaining q15_t data */
+  tapCnt = (numTaps - 1U) % 0x4U;
+
+  /* copy data */
+  while (tapCnt > 0U)
+  {
+    *pStateCurnt++ = *pState++;
+
+    /* Decrement the loop counter */
+    tapCnt--;
+  }
+
+#else
+
+  /* Run the below code for Cortex-M0 */
+
+  /* S->pState points to buffer which contains previous frame (numTaps - 1) samples */
+  /* pStateCurnt points to the location where the new input data should be written */
+  pStateCurnt = &(S->pState[(numTaps - 1U)]);
+
+  /* Loop over blockSize number of values */
+  blkCnt = blockSize;
+
+  while (blkCnt > 0U)
+  {
+    /* Copy the new input sample into the state buffer */
+    *pStateCurnt++ = *pSrc++;
+
+    /* Initialize pState pointer */
+    px = pState;
+
+    /* Initialize pCoeffs pointer */
+    pb = pCoeffs;
+
+    /* Set the accumulator to zero */
+    acc = 0;
+
+    /* Loop over numTaps number of values */
+    tapCnt = numTaps;
+
+    while (tapCnt > 0U)
+    {
+      /* Perform the multiply-accumulate */
+      acc += (q63_t) ((q31_t) (*px++) * (*pb++));
+
+      /* Decrement the loop counter */
+      tapCnt--;
+    }
+
+    /* Calc lower part of acc */
+    acc_l = acc & 0xffffffff;
+
+    /* Calc upper part of acc */
+    acc_h = (acc >> 32) & 0xffffffff;
+
+    /* Apply shift for lower part of acc and upper part of acc */
+    acc = (uint32_t) acc_l >> lShift | acc_h << uShift;
+
+    /* Converting the result to 1.15 format and saturate the output */
+    acc = __SSAT(acc, 16);
+
+    /* Store the result from accumulator into the destination buffer. */
+    *pOut++ = (q15_t) acc;
+
+    /* Compute and store error */
+    e = *pRef++ - (q15_t) acc;
+
+    *pErr++ = (q15_t) e;
+
+    /* Compute alpha i.e. intermediate constant for taps update */
+    alpha = (q15_t) (((q31_t) e * (mu)) >> 15);
+
+    /* Initialize pState pointer */
+    /* Advance state pointer by 1 for the next sample */
+    px = pState++;
+
+    /* Initialize pCoeffs pointer */
+    pb = pCoeffs;
+
+    /* Loop over numTaps number of values */
+    tapCnt = numTaps;
+
+    while (tapCnt > 0U)
+    {
+      /* Perform the multiply-accumulate */
+      coef = (q31_t) * pb + (((q31_t) alpha * (*px++)) >> 15);
+      *pb++ = (q15_t) __SSAT((coef), 16);
+
+      /* Decrement the loop counter */
+      tapCnt--;
+    }
+
+    /* Decrement the loop counter */
+    blkCnt--;
+
+  }
+
+  /* Processing is complete. Now copy the last numTaps - 1 samples to the
+     start of the state buffer. This prepares the state buffer for the
+     next function call. */
+
+  /* Points to the start of the pState buffer */
+  pStateCurnt = S->pState;
+
+  /*  Copy (numTaps - 1U) samples  */
+  tapCnt = (numTaps - 1U);
+
+  /* Copy the data */
+  while (tapCnt > 0U)
+  {
+    *pStateCurnt++ = *pState++;
+
+    /* Decrement the loop counter */
+    tapCnt--;
+  }
+
+#endif /*   #if defined (ARM_MATH_DSP) */
+
+}
+
+/**
+   * @} end of LMS group
+   */