1 /**
2 ******************************************************************************
3 * @file stm32wbaxx_ll_usart.c
4 * @author MCD Application Team
5 * @brief USART LL module driver.
6 ******************************************************************************
7 * @attention
8 *
9 * Copyright (c) 2022 STMicroelectronics.
10 * All rights reserved.
11 *
12 * This software is licensed under terms that can be found in the LICENSE file
13 * in the root directory of this software component.
14 * If no LICENSE file comes with this software, it is provided AS-IS.
15 *
16 ******************************************************************************
17 */
18 #if defined(USE_FULL_LL_DRIVER)
19
20 /* Includes ------------------------------------------------------------------*/
21 #include "stm32wbaxx_ll_usart.h"
22 #include "stm32wbaxx_ll_rcc.h"
23 #include "stm32wbaxx_ll_bus.h"
24 #ifdef USE_FULL_ASSERT
25 #include "stm32_assert.h"
26 #else
27 #define assert_param(expr) ((void)0U)
28 #endif /* USE_FULL_ASSERT */
29
30 /** @addtogroup STM32WBAxx_LL_Driver
31 * @{
32 */
33
34 #if defined(USART1) || defined(USART2)
35
36 /** @addtogroup USART_LL
37 * @{
38 */
39
40 /* Private types -------------------------------------------------------------*/
41 /* Private variables ---------------------------------------------------------*/
42 /* Private constants ---------------------------------------------------------*/
43 /** @addtogroup USART_LL_Private_Constants
44 * @{
45 */
46
47 /* Definition of default baudrate value used for USART initialisation */
48 #define USART_DEFAULT_BAUDRATE (9600U)
49
50 /**
51 * @}
52 */
53
54 /* Private macros ------------------------------------------------------------*/
55 /** @addtogroup USART_LL_Private_Macros
56 * @{
57 */
58
59 #define IS_LL_USART_PRESCALER(__VALUE__) (((__VALUE__) == LL_USART_PRESCALER_DIV1) \
60 || ((__VALUE__) == LL_USART_PRESCALER_DIV2) \
61 || ((__VALUE__) == LL_USART_PRESCALER_DIV4) \
62 || ((__VALUE__) == LL_USART_PRESCALER_DIV6) \
63 || ((__VALUE__) == LL_USART_PRESCALER_DIV8) \
64 || ((__VALUE__) == LL_USART_PRESCALER_DIV10) \
65 || ((__VALUE__) == LL_USART_PRESCALER_DIV12) \
66 || ((__VALUE__) == LL_USART_PRESCALER_DIV16) \
67 || ((__VALUE__) == LL_USART_PRESCALER_DIV32) \
68 || ((__VALUE__) == LL_USART_PRESCALER_DIV64) \
69 || ((__VALUE__) == LL_USART_PRESCALER_DIV128) \
70 || ((__VALUE__) == LL_USART_PRESCALER_DIV256))
71
72 /* __BAUDRATE__ The maximum Baud Rate is derived from the maximum clock available
73 * divided by the smallest oversampling used on the USART (i.e. 8) */
74 #define IS_LL_USART_BAUDRATE(__BAUDRATE__) ((__BAUDRATE__) <= 12500000U)
75
76 /* __VALUE__ In case of oversampling by 16 and 8, BRR content must be greater than or equal to 16d. */
77 #define IS_LL_USART_BRR_MIN(__VALUE__) ((__VALUE__) >= 16U)
78
79 #define IS_LL_USART_DIRECTION(__VALUE__) (((__VALUE__) == LL_USART_DIRECTION_NONE) \
80 || ((__VALUE__) == LL_USART_DIRECTION_RX) \
81 || ((__VALUE__) == LL_USART_DIRECTION_TX) \
82 || ((__VALUE__) == LL_USART_DIRECTION_TX_RX))
83
84 #define IS_LL_USART_PARITY(__VALUE__) (((__VALUE__) == LL_USART_PARITY_NONE) \
85 || ((__VALUE__) == LL_USART_PARITY_EVEN) \
86 || ((__VALUE__) == LL_USART_PARITY_ODD))
87
88 #define IS_LL_USART_DATAWIDTH(__VALUE__) (((__VALUE__) == LL_USART_DATAWIDTH_7B) \
89 || ((__VALUE__) == LL_USART_DATAWIDTH_8B) \
90 || ((__VALUE__) == LL_USART_DATAWIDTH_9B))
91
92 #define IS_LL_USART_OVERSAMPLING(__VALUE__) (((__VALUE__) == LL_USART_OVERSAMPLING_16) \
93 || ((__VALUE__) == LL_USART_OVERSAMPLING_8))
94
95 #define IS_LL_USART_LASTBITCLKOUTPUT(__VALUE__) (((__VALUE__) == LL_USART_LASTCLKPULSE_NO_OUTPUT) \
96 || ((__VALUE__) == LL_USART_LASTCLKPULSE_OUTPUT))
97
98 #define IS_LL_USART_CLOCKPHASE(__VALUE__) (((__VALUE__) == LL_USART_PHASE_1EDGE) \
99 || ((__VALUE__) == LL_USART_PHASE_2EDGE))
100
101 #define IS_LL_USART_CLOCKPOLARITY(__VALUE__) (((__VALUE__) == LL_USART_POLARITY_LOW) \
102 || ((__VALUE__) == LL_USART_POLARITY_HIGH))
103
104 #define IS_LL_USART_CLOCKOUTPUT(__VALUE__) (((__VALUE__) == LL_USART_CLOCK_DISABLE) \
105 || ((__VALUE__) == LL_USART_CLOCK_ENABLE))
106
107 #define IS_LL_USART_STOPBITS(__VALUE__) (((__VALUE__) == LL_USART_STOPBITS_0_5) \
108 || ((__VALUE__) == LL_USART_STOPBITS_1) \
109 || ((__VALUE__) == LL_USART_STOPBITS_1_5) \
110 || ((__VALUE__) == LL_USART_STOPBITS_2))
111
112 #define IS_LL_USART_HWCONTROL(__VALUE__) (((__VALUE__) == LL_USART_HWCONTROL_NONE) \
113 || ((__VALUE__) == LL_USART_HWCONTROL_RTS) \
114 || ((__VALUE__) == LL_USART_HWCONTROL_CTS) \
115 || ((__VALUE__) == LL_USART_HWCONTROL_RTS_CTS))
116
117 /**
118 * @}
119 */
120
121 /* Private function prototypes -----------------------------------------------*/
122
123 /* Exported functions --------------------------------------------------------*/
124 /** @addtogroup USART_LL_Exported_Functions
125 * @{
126 */
127
128 /** @addtogroup USART_LL_EF_Init
129 * @{
130 */
131
132 /**
133 * @brief De-initialize USART registers (Registers restored to their default values).
134 * @param USARTx USART Instance
135 * @retval An ErrorStatus enumeration value:
136 * - SUCCESS: USART registers are de-initialized
137 * - ERROR: USART registers are not de-initialized
138 */
LL_USART_DeInit(const USART_TypeDef * USARTx)139 ErrorStatus LL_USART_DeInit(const USART_TypeDef *USARTx)
140 {
141 ErrorStatus status = SUCCESS;
142
143 /* Check the parameters */
144 assert_param(IS_UART_INSTANCE(USARTx));
145
146 if (USARTx == USART1)
147 {
148 /* Force reset of USART clock */
149 LL_APB2_GRP1_ForceReset(LL_APB2_GRP1_PERIPH_USART1);
150
151 /* Release reset of USART clock */
152 LL_APB2_GRP1_ReleaseReset(LL_APB2_GRP1_PERIPH_USART1);
153 }
154 #if defined(USART2)
155 else if (USARTx == USART2)
156 {
157 /* Force reset of USART clock */
158 LL_APB1_GRP1_ForceReset(LL_APB1_GRP1_PERIPH_USART2);
159
160 /* Release reset of USART clock */
161 LL_APB1_GRP1_ReleaseReset(LL_APB1_GRP1_PERIPH_USART2);
162 }
163 #endif /* USART2 */
164 else
165 {
166 status = ERROR;
167 }
168
169 return (status);
170 }
171
172 /**
173 * @brief Initialize USART registers according to the specified
174 * parameters in USART_InitStruct.
175 * @note As some bits in USART configuration registers can only be written when
176 * the USART is disabled (USART_CR1_UE bit =0), USART Peripheral should be in disabled state prior calling
177 * this function. Otherwise, ERROR result will be returned.
178 * @note Baud rate value stored in USART_InitStruct BaudRate field, should be valid (different from 0).
179 * @param USARTx USART Instance
180 * @param USART_InitStruct pointer to a LL_USART_InitTypeDef structure
181 * that contains the configuration information for the specified USART peripheral.
182 * @retval An ErrorStatus enumeration value:
183 * - SUCCESS: USART registers are initialized according to USART_InitStruct content
184 * - ERROR: Problem occurred during USART Registers initialization
185 */
LL_USART_Init(USART_TypeDef * USARTx,const LL_USART_InitTypeDef * USART_InitStruct)186 ErrorStatus LL_USART_Init(USART_TypeDef *USARTx, const LL_USART_InitTypeDef *USART_InitStruct)
187 {
188 ErrorStatus status = ERROR;
189 uint32_t periphclk = LL_RCC_PERIPH_FREQUENCY_NO;
190
191 /* Check the parameters */
192 assert_param(IS_UART_INSTANCE(USARTx));
193 assert_param(IS_LL_USART_PRESCALER(USART_InitStruct->PrescalerValue));
194 assert_param(IS_LL_USART_BAUDRATE(USART_InitStruct->BaudRate));
195 assert_param(IS_LL_USART_DATAWIDTH(USART_InitStruct->DataWidth));
196 assert_param(IS_LL_USART_STOPBITS(USART_InitStruct->StopBits));
197 assert_param(IS_LL_USART_PARITY(USART_InitStruct->Parity));
198 assert_param(IS_LL_USART_DIRECTION(USART_InitStruct->TransferDirection));
199 assert_param(IS_LL_USART_HWCONTROL(USART_InitStruct->HardwareFlowControl));
200 assert_param(IS_LL_USART_OVERSAMPLING(USART_InitStruct->OverSampling));
201
202 /* USART needs to be in disabled state, in order to be able to configure some bits in
203 CRx registers */
204 if (LL_USART_IsEnabled(USARTx) == 0U)
205 {
206 /*---------------------------- USART CR1 Configuration ---------------------
207 * Configure USARTx CR1 (USART Word Length, Parity, Mode and Oversampling bits) with parameters:
208 * - DataWidth: USART_CR1_M bits according to USART_InitStruct->DataWidth value
209 * - Parity: USART_CR1_PCE, USART_CR1_PS bits according to USART_InitStruct->Parity value
210 * - TransferDirection: USART_CR1_TE, USART_CR1_RE bits according to USART_InitStruct->TransferDirection value
211 * - Oversampling: USART_CR1_OVER8 bit according to USART_InitStruct->OverSampling value.
212 */
213 MODIFY_REG(USARTx->CR1,
214 (USART_CR1_M | USART_CR1_PCE | USART_CR1_PS |
215 USART_CR1_TE | USART_CR1_RE | USART_CR1_OVER8),
216 (USART_InitStruct->DataWidth | USART_InitStruct->Parity |
217 USART_InitStruct->TransferDirection | USART_InitStruct->OverSampling));
218
219 /*---------------------------- USART CR2 Configuration ---------------------
220 * Configure USARTx CR2 (Stop bits) with parameters:
221 * - Stop Bits: USART_CR2_STOP bits according to USART_InitStruct->StopBits value.
222 * - CLKEN, CPOL, CPHA and LBCL bits are to be configured using LL_USART_ClockInit().
223 */
224 LL_USART_SetStopBitsLength(USARTx, USART_InitStruct->StopBits);
225
226 /*---------------------------- USART CR3 Configuration ---------------------
227 * Configure USARTx CR3 (Hardware Flow Control) with parameters:
228 * - HardwareFlowControl: USART_CR3_RTSE, USART_CR3_CTSE bits according to
229 * USART_InitStruct->HardwareFlowControl value.
230 */
231 LL_USART_SetHWFlowCtrl(USARTx, USART_InitStruct->HardwareFlowControl);
232
233 /*---------------------------- USART BRR Configuration ---------------------
234 * Retrieve Clock frequency used for USART Peripheral
235 */
236 if (USARTx == USART1)
237 {
238 periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART1_CLKSOURCE);
239 }
240 #if defined(USART2)
241 else if (USARTx == USART2)
242 {
243 periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART2_CLKSOURCE);
244 }
245 #endif /* USART2 */
246 else
247 {
248 /* Nothing to do, as error code is already assigned to ERROR value */
249 }
250
251 /* Configure the USART Baud Rate :
252 - prescaler value is required
253 - valid baud rate value (different from 0) is required
254 - Peripheral clock as returned by RCC service, should be valid (different from 0).
255 */
256 if ((periphclk != LL_RCC_PERIPH_FREQUENCY_NO)
257 && (USART_InitStruct->BaudRate != 0U))
258 {
259 status = SUCCESS;
260 LL_USART_SetBaudRate(USARTx,
261 periphclk,
262 USART_InitStruct->PrescalerValue,
263 USART_InitStruct->OverSampling,
264 USART_InitStruct->BaudRate);
265
266 /* Check BRR is greater than or equal to 16d */
267 assert_param(IS_LL_USART_BRR_MIN(USARTx->BRR));
268 }
269
270 /*---------------------------- USART PRESC Configuration -----------------------
271 * Configure USARTx PRESC (Prescaler) with parameters:
272 * - PrescalerValue: USART_PRESC_PRESCALER bits according to USART_InitStruct->PrescalerValue value.
273 */
274 LL_USART_SetPrescaler(USARTx, USART_InitStruct->PrescalerValue);
275 }
276 /* Endif (=> USART not in Disabled state => return ERROR) */
277
278 return (status);
279 }
280
281 /**
282 * @brief Set each @ref LL_USART_InitTypeDef field to default value.
283 * @param USART_InitStruct pointer to a @ref LL_USART_InitTypeDef structure
284 * whose fields will be set to default values.
285 * @retval None
286 */
287
LL_USART_StructInit(LL_USART_InitTypeDef * USART_InitStruct)288 void LL_USART_StructInit(LL_USART_InitTypeDef *USART_InitStruct)
289 {
290 /* Set USART_InitStruct fields to default values */
291 USART_InitStruct->PrescalerValue = LL_USART_PRESCALER_DIV1;
292 USART_InitStruct->BaudRate = USART_DEFAULT_BAUDRATE;
293 USART_InitStruct->DataWidth = LL_USART_DATAWIDTH_8B;
294 USART_InitStruct->StopBits = LL_USART_STOPBITS_1;
295 USART_InitStruct->Parity = LL_USART_PARITY_NONE ;
296 USART_InitStruct->TransferDirection = LL_USART_DIRECTION_TX_RX;
297 USART_InitStruct->HardwareFlowControl = LL_USART_HWCONTROL_NONE;
298 USART_InitStruct->OverSampling = LL_USART_OVERSAMPLING_16;
299 }
300
301 /**
302 * @brief Initialize USART Clock related settings according to the
303 * specified parameters in the USART_ClockInitStruct.
304 * @note As some bits in USART configuration registers can only be written when
305 * the USART is disabled (USART_CR1_UE bit =0), USART Peripheral should be in disabled state prior calling
306 * this function. Otherwise, ERROR result will be returned.
307 * @param USARTx USART Instance
308 * @param USART_ClockInitStruct pointer to a @ref LL_USART_ClockInitTypeDef structure
309 * that contains the Clock configuration information for the specified USART peripheral.
310 * @retval An ErrorStatus enumeration value:
311 * - SUCCESS: USART registers related to Clock settings are initialized according
312 * to USART_ClockInitStruct content
313 * - ERROR: Problem occurred during USART Registers initialization
314 */
LL_USART_ClockInit(USART_TypeDef * USARTx,const LL_USART_ClockInitTypeDef * USART_ClockInitStruct)315 ErrorStatus LL_USART_ClockInit(USART_TypeDef *USARTx, const LL_USART_ClockInitTypeDef *USART_ClockInitStruct)
316 {
317 ErrorStatus status = SUCCESS;
318
319 /* Check USART Instance and Clock signal output parameters */
320 assert_param(IS_UART_INSTANCE(USARTx));
321 assert_param(IS_LL_USART_CLOCKOUTPUT(USART_ClockInitStruct->ClockOutput));
322
323 /* USART needs to be in disabled state, in order to be able to configure some bits in
324 CRx registers */
325 if (LL_USART_IsEnabled(USARTx) == 0U)
326 {
327 /* Ensure USART instance is USART capable */
328 assert_param(IS_USART_INSTANCE(USARTx));
329
330 /* Check clock related parameters */
331 assert_param(IS_LL_USART_CLOCKPOLARITY(USART_ClockInitStruct->ClockPolarity));
332 assert_param(IS_LL_USART_CLOCKPHASE(USART_ClockInitStruct->ClockPhase));
333 assert_param(IS_LL_USART_LASTBITCLKOUTPUT(USART_ClockInitStruct->LastBitClockPulse));
334
335 /*---------------------------- USART CR2 Configuration -----------------------
336 * Configure USARTx CR2 (Clock signal related bits) with parameters:
337 * - Clock Output: USART_CR2_CLKEN bit according to USART_ClockInitStruct->ClockOutput value
338 * - Clock Polarity: USART_CR2_CPOL bit according to USART_ClockInitStruct->ClockPolarity value
339 * - Clock Phase: USART_CR2_CPHA bit according to USART_ClockInitStruct->ClockPhase value
340 * - Last Bit Clock Pulse Output: USART_CR2_LBCL bit according to USART_ClockInitStruct->LastBitClockPulse value.
341 */
342 MODIFY_REG(USARTx->CR2,
343 USART_CR2_CLKEN | USART_CR2_CPHA | USART_CR2_CPOL | USART_CR2_LBCL,
344 USART_ClockInitStruct->ClockOutput | USART_ClockInitStruct->ClockPolarity |
345 USART_ClockInitStruct->ClockPhase | USART_ClockInitStruct->LastBitClockPulse);
346 }
347 /* Else (USART not in Disabled state => return ERROR */
348 else
349 {
350 status = ERROR;
351 }
352
353 return (status);
354 }
355
356 /**
357 * @brief Set each field of a @ref LL_USART_ClockInitTypeDef type structure to default value.
358 * @param USART_ClockInitStruct pointer to a @ref LL_USART_ClockInitTypeDef structure
359 * whose fields will be set to default values.
360 * @retval None
361 */
LL_USART_ClockStructInit(LL_USART_ClockInitTypeDef * USART_ClockInitStruct)362 void LL_USART_ClockStructInit(LL_USART_ClockInitTypeDef *USART_ClockInitStruct)
363 {
364 /* Set LL_USART_ClockInitStruct fields with default values */
365 USART_ClockInitStruct->ClockOutput = LL_USART_CLOCK_DISABLE;
366 USART_ClockInitStruct->ClockPolarity = LL_USART_POLARITY_LOW; /* Not relevant when ClockOutput =
367 LL_USART_CLOCK_DISABLE */
368 USART_ClockInitStruct->ClockPhase = LL_USART_PHASE_1EDGE; /* Not relevant when ClockOutput =
369 LL_USART_CLOCK_DISABLE */
370 USART_ClockInitStruct->LastBitClockPulse = LL_USART_LASTCLKPULSE_NO_OUTPUT; /* Not relevant when ClockOutput =
371 LL_USART_CLOCK_DISABLE */
372 }
373
374 /**
375 * @}
376 */
377
378 /**
379 * @}
380 */
381
382 /**
383 * @}
384 */
385
386 #endif /* USART1 || USART2 */
387
388 /**
389 * @}
390 */
391
392 #endif /* USE_FULL_LL_DRIVER */
393
394
395
