1 /**
2 ******************************************************************************
3 * @file stm32l0xx_hal_crc_ex.c
4 * @author MCD Application Team
5 * @brief Extended CRC HAL module driver.
6 * This file provides firmware functions to manage the extended
7 * functionalities of the CRC peripheral.
8 *
9 ******************************************************************************
10 * @attention
11 *
12 * Copyright (c) 2016 STMicroelectronics.
13 * All rights reserved.
14 *
15 * This software is licensed under terms that can be found in the LICENSE file
16 * in the root directory of this software component.
17 * If no LICENSE file comes with this software, it is provided AS-IS.
18 *
19 ******************************************************************************
20 @verbatim
21 ================================================================================
22 ##### How to use this driver #####
23 ================================================================================
24 [..]
25 (+) Set user-defined generating polynomial through HAL_CRCEx_Polynomial_Set()
26 (+) Configure Input or Output data inversion
27
28 @endverbatim
29 ******************************************************************************
30 */
31
32 /* Includes ------------------------------------------------------------------*/
33 #include "stm32l0xx_hal.h"
34
35 /** @addtogroup STM32L0xx_HAL_Driver
36 * @{
37 */
38
39 /** @defgroup CRCEx CRCEx
40 * @brief CRC Extended HAL module driver
41 * @{
42 */
43
44 #ifdef HAL_CRC_MODULE_ENABLED
45
46 /* Private typedef -----------------------------------------------------------*/
47 /* Private define ------------------------------------------------------------*/
48 /* Private macro -------------------------------------------------------------*/
49 /* Private variables ---------------------------------------------------------*/
50 /* Private function prototypes -----------------------------------------------*/
51 /* Exported functions --------------------------------------------------------*/
52
53 /** @defgroup CRCEx_Exported_Functions CRC Extended Exported Functions
54 * @{
55 */
56
57 /** @defgroup CRCEx_Exported_Functions_Group1 Extended Initialization/de-initialization functions
58 * @brief Extended Initialization and Configuration functions.
59 *
60 @verbatim
61 ===============================================================================
62 ##### Extended configuration functions #####
63 ===============================================================================
64 [..] This section provides functions allowing to:
65 (+) Configure the generating polynomial
66 (+) Configure the input data inversion
67 (+) Configure the output data inversion
68
69 @endverbatim
70 * @{
71 */
72
73
74 /**
75 * @brief Initialize the CRC polynomial if different from default one.
76 * @param hcrc CRC handle
77 * @param Pol CRC generating polynomial (7, 8, 16 or 32-bit long).
78 * This parameter is written in normal representation, e.g.
79 * @arg for a polynomial of degree 7, X^7 + X^6 + X^5 + X^2 + 1 is written 0x65
80 * @arg for a polynomial of degree 16, X^16 + X^12 + X^5 + 1 is written 0x1021
81 * @param PolyLength CRC polynomial length.
82 * This parameter can be one of the following values:
83 * @arg @ref CRC_POLYLENGTH_7B 7-bit long CRC (generating polynomial of degree 7)
84 * @arg @ref CRC_POLYLENGTH_8B 8-bit long CRC (generating polynomial of degree 8)
85 * @arg @ref CRC_POLYLENGTH_16B 16-bit long CRC (generating polynomial of degree 16)
86 * @arg @ref CRC_POLYLENGTH_32B 32-bit long CRC (generating polynomial of degree 32)
87 * @retval HAL status
88 */
HAL_CRCEx_Polynomial_Set(CRC_HandleTypeDef * hcrc,uint32_t Pol,uint32_t PolyLength)89 HAL_StatusTypeDef HAL_CRCEx_Polynomial_Set(CRC_HandleTypeDef *hcrc, uint32_t Pol, uint32_t PolyLength)
90 {
91 HAL_StatusTypeDef status = HAL_OK;
92 uint32_t msb = 31U; /* polynomial degree is 32 at most, so msb is initialized to max value */
93
94 /* Check the parameters */
95 assert_param(IS_CRC_POL_LENGTH(PolyLength));
96
97 /* Ensure that the generating polynomial is odd */
98 if ((Pol & (uint32_t)(0x1U)) == 0U)
99 {
100 status = HAL_ERROR;
101 }
102 else
103 {
104 /* check polynomial definition vs polynomial size:
105 * polynomial length must be aligned with polynomial
106 * definition. HAL_ERROR is reported if Pol degree is
107 * larger than that indicated by PolyLength.
108 * Look for MSB position: msb will contain the degree of
109 * the second to the largest polynomial member. E.g., for
110 * X^7 + X^6 + X^5 + X^2 + 1, msb = 6. */
111 while ((msb-- > 0U) && ((Pol & ((uint32_t)(0x1U) << (msb & 0x1FU))) == 0U))
112 {
113 }
114
115 switch (PolyLength)
116 {
117
118 case CRC_POLYLENGTH_7B:
119 if (msb >= HAL_CRC_LENGTH_7B)
120 {
121 status = HAL_ERROR;
122 }
123 break;
124 case CRC_POLYLENGTH_8B:
125 if (msb >= HAL_CRC_LENGTH_8B)
126 {
127 status = HAL_ERROR;
128 }
129 break;
130 case CRC_POLYLENGTH_16B:
131 if (msb >= HAL_CRC_LENGTH_16B)
132 {
133 status = HAL_ERROR;
134 }
135 break;
136
137 case CRC_POLYLENGTH_32B:
138 /* no polynomial definition vs. polynomial length issue possible */
139 break;
140 default:
141 status = HAL_ERROR;
142 break;
143 }
144 }
145 if (status == HAL_OK)
146 {
147 /* set generating polynomial */
148 WRITE_REG(hcrc->Instance->POL, Pol);
149
150 /* set generating polynomial size */
151 MODIFY_REG(hcrc->Instance->CR, CRC_CR_POLYSIZE, PolyLength);
152 }
153 /* Return function status */
154 return status;
155 }
156
157 /**
158 * @brief Set the Reverse Input data mode.
159 * @param hcrc CRC handle
160 * @param InputReverseMode Input Data inversion mode.
161 * This parameter can be one of the following values:
162 * @arg @ref CRC_INPUTDATA_INVERSION_NONE no change in bit order (default value)
163 * @arg @ref CRC_INPUTDATA_INVERSION_BYTE Byte-wise bit reversal
164 * @arg @ref CRC_INPUTDATA_INVERSION_HALFWORD HalfWord-wise bit reversal
165 * @arg @ref CRC_INPUTDATA_INVERSION_WORD Word-wise bit reversal
166 * @retval HAL status
167 */
HAL_CRCEx_Input_Data_Reverse(CRC_HandleTypeDef * hcrc,uint32_t InputReverseMode)168 HAL_StatusTypeDef HAL_CRCEx_Input_Data_Reverse(CRC_HandleTypeDef *hcrc, uint32_t InputReverseMode)
169 {
170 /* Check the parameters */
171 assert_param(IS_CRC_INPUTDATA_INVERSION_MODE(InputReverseMode));
172
173 /* Change CRC peripheral state */
174 hcrc->State = HAL_CRC_STATE_BUSY;
175
176 /* set input data inversion mode */
177 MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_IN, InputReverseMode);
178 /* Change CRC peripheral state */
179 hcrc->State = HAL_CRC_STATE_READY;
180
181 /* Return function status */
182 return HAL_OK;
183 }
184
185 /**
186 * @brief Set the Reverse Output data mode.
187 * @param hcrc CRC handle
188 * @param OutputReverseMode Output Data inversion mode.
189 * This parameter can be one of the following values:
190 * @arg @ref CRC_OUTPUTDATA_INVERSION_DISABLE no CRC inversion (default value)
191 * @arg @ref CRC_OUTPUTDATA_INVERSION_ENABLE bit-level inversion (e.g. for a 8-bit CRC: 0xB5 becomes 0xAD)
192 * @retval HAL status
193 */
HAL_CRCEx_Output_Data_Reverse(CRC_HandleTypeDef * hcrc,uint32_t OutputReverseMode)194 HAL_StatusTypeDef HAL_CRCEx_Output_Data_Reverse(CRC_HandleTypeDef *hcrc, uint32_t OutputReverseMode)
195 {
196 /* Check the parameters */
197 assert_param(IS_CRC_OUTPUTDATA_INVERSION_MODE(OutputReverseMode));
198
199 /* Change CRC peripheral state */
200 hcrc->State = HAL_CRC_STATE_BUSY;
201
202 /* set output data inversion mode */
203 MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_OUT, OutputReverseMode);
204
205 /* Change CRC peripheral state */
206 hcrc->State = HAL_CRC_STATE_READY;
207
208 /* Return function status */
209 return HAL_OK;
210 }
211
212
213
214
215 /**
216 * @}
217 */
218
219
220 /**
221 * @}
222 */
223
224
225 #endif /* HAL_CRC_MODULE_ENABLED */
226 /**
227 * @}
228 */
229
230 /**
231 * @}
232 */
233
