1 /* ----------------------------------------------------------------------
2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
4 * $Date: 17. January 2013
7 * Project: CMSIS DSP Library
8 * Title: arm_pid_init_q15.c
10 * Description: Q15 PID Control initialization function
12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
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18 * notice, this list of conditions and the following disclaimer.
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21 * the documentation and/or other materials provided with the
23 * - Neither the name of ARM LIMITED nor the names of its contributors
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27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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39 * -------------------------------------------------------------------- */
50 * @param[in,out] *S points to an instance of the Q15 PID structure.
51 * @param[in] resetStateFlag flag to reset the state. 0 = no change in state 1 = reset the state.
55 * The <code>resetStateFlag</code> specifies whether to set state to zero or not. \n
56 * The function computes the structure fields: <code>A0</code>, <code>A1</code> <code>A2</code>
57 * using the proportional gain( \c Kp), integral gain( \c Ki) and derivative gain( \c Kd)
58 * also sets the state variables to all zeros.
61 void arm_pid_init_q15(
62 arm_pid_instance_q15 * S,
63 int32_t resetStateFlag)
66 #ifndef ARM_MATH_CM0_FAMILY
68 /* Run the below code for Cortex-M4 and Cortex-M3 */
70 /* Derived coefficient A0 */
71 S->A0 = __QADD16(__QADD16(S->Kp, S->Ki), S->Kd);
73 /* Derived coefficients and pack into A1 */
75 #ifndef ARM_MATH_BIG_ENDIAN
77 S->A1 = __PKHBT(-__QADD16(__QADD16(S->Kd, S->Kd), S->Kp), S->Kd, 16);
81 S->A1 = __PKHBT(S->Kd, -__QADD16(__QADD16(S->Kd, S->Kd), S->Kp), 16);
83 #endif /* #ifndef ARM_MATH_BIG_ENDIAN */
85 /* Check whether state needs reset or not */
88 /* Clear the state buffer. The size will be always 3 samples */
89 memset(S->state, 0, 3u * sizeof(q15_t));
94 /* Run the below code for Cortex-M0 */
96 q31_t temp; /*to store the sum */
98 /* Derived coefficient A0 */
99 temp = S->Kp + S->Ki + S->Kd;
100 S->A0 = (q15_t) __SSAT(temp, 16);
102 /* Derived coefficients and pack into A1 */
103 temp = -(S->Kd + S->Kd + S->Kp);
104 S->A1 = (q15_t) __SSAT(temp, 16);
109 /* Check whether state needs reset or not */
112 /* Clear the state buffer. The size will be always 3 samples */
113 memset(S->state, 0, 3u * sizeof(q15_t));
116 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
121 * @} end of PID group