1 /**
2 ******************************************************************************
3 * @file stm32wbxx_ll_usart.c
4 * @author MCD Application Team
5 * @brief USART LL module driver.
6 ******************************************************************************
7 * @attention
8 *
9 * Copyright (c) 2019 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 "stm32wbxx_ll_usart.h"
22 #include "stm32wbxx_ll_rcc.h"
23 #include "stm32wbxx_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 STM32WBxx_LL_Driver
31 * @{
32 */
33
34 #if defined (USART1)
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__) <= 8000000U)
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 else
155 {
156 status = ERROR;
157 }
158
159 return (status);
160 }
161
162 /**
163 * @brief Initialize USART registers according to the specified
164 * parameters in USART_InitStruct.
165 * @note As some bits in USART configuration registers can only be written when
166 * the USART is disabled (USART_CR1_UE bit =0), USART Peripheral should be in disabled state prior calling
167 * this function. Otherwise, ERROR result will be returned.
168 * @note Baud rate value stored in USART_InitStruct BaudRate field, should be valid (different from 0).
169 * @param USARTx USART Instance
170 * @param USART_InitStruct pointer to a LL_USART_InitTypeDef structure
171 * that contains the configuration information for the specified USART peripheral.
172 * @retval An ErrorStatus enumeration value:
173 * - SUCCESS: USART registers are initialized according to USART_InitStruct content
174 * - ERROR: Problem occurred during USART Registers initialization
175 */
LL_USART_Init(USART_TypeDef * USARTx,const LL_USART_InitTypeDef * USART_InitStruct)176 ErrorStatus LL_USART_Init(USART_TypeDef *USARTx, const LL_USART_InitTypeDef *USART_InitStruct)
177 {
178 ErrorStatus status = ERROR;
179 uint32_t periphclk = LL_RCC_PERIPH_FREQUENCY_NO;
180
181 /* Check the parameters */
182 assert_param(IS_UART_INSTANCE(USARTx));
183 assert_param(IS_LL_USART_PRESCALER(USART_InitStruct->PrescalerValue));
184 assert_param(IS_LL_USART_BAUDRATE(USART_InitStruct->BaudRate));
185 assert_param(IS_LL_USART_DATAWIDTH(USART_InitStruct->DataWidth));
186 assert_param(IS_LL_USART_STOPBITS(USART_InitStruct->StopBits));
187 assert_param(IS_LL_USART_PARITY(USART_InitStruct->Parity));
188 assert_param(IS_LL_USART_DIRECTION(USART_InitStruct->TransferDirection));
189 assert_param(IS_LL_USART_HWCONTROL(USART_InitStruct->HardwareFlowControl));
190 assert_param(IS_LL_USART_OVERSAMPLING(USART_InitStruct->OverSampling));
191
192 /* USART needs to be in disabled state, in order to be able to configure some bits in
193 CRx registers */
194 if (LL_USART_IsEnabled(USARTx) == 0U)
195 {
196 /*---------------------------- USART CR1 Configuration ---------------------
197 * Configure USARTx CR1 (USART Word Length, Parity, Mode and Oversampling bits) with parameters:
198 * - DataWidth: USART_CR1_M bits according to USART_InitStruct->DataWidth value
199 * - Parity: USART_CR1_PCE, USART_CR1_PS bits according to USART_InitStruct->Parity value
200 * - TransferDirection: USART_CR1_TE, USART_CR1_RE bits according to USART_InitStruct->TransferDirection value
201 * - Oversampling: USART_CR1_OVER8 bit according to USART_InitStruct->OverSampling value.
202 */
203 MODIFY_REG(USARTx->CR1,
204 (USART_CR1_M | USART_CR1_PCE | USART_CR1_PS |
205 USART_CR1_TE | USART_CR1_RE | USART_CR1_OVER8),
206 (USART_InitStruct->DataWidth | USART_InitStruct->Parity |
207 USART_InitStruct->TransferDirection | USART_InitStruct->OverSampling));
208
209 /*---------------------------- USART CR2 Configuration ---------------------
210 * Configure USARTx CR2 (Stop bits) with parameters:
211 * - Stop Bits: USART_CR2_STOP bits according to USART_InitStruct->StopBits value.
212 * - CLKEN, CPOL, CPHA and LBCL bits are to be configured using LL_USART_ClockInit().
213 */
214 LL_USART_SetStopBitsLength(USARTx, USART_InitStruct->StopBits);
215
216 /*---------------------------- USART CR3 Configuration ---------------------
217 * Configure USARTx CR3 (Hardware Flow Control) with parameters:
218 * - HardwareFlowControl: USART_CR3_RTSE, USART_CR3_CTSE bits according to
219 * USART_InitStruct->HardwareFlowControl value.
220 */
221 LL_USART_SetHWFlowCtrl(USARTx, USART_InitStruct->HardwareFlowControl);
222
223 /*---------------------------- USART BRR Configuration ---------------------
224 * Retrieve Clock frequency used for USART Peripheral
225 */
226 if (USARTx == USART1)
227 {
228 periphclk = LL_RCC_GetUSARTClockFreq(LL_RCC_USART1_CLKSOURCE);
229 }
230 else
231 {
232 /* Nothing to do, as error code is already assigned to ERROR value */
233 }
234
235 /* Configure the USART Baud Rate :
236 - prescaler value is required
237 - valid baud rate value (different from 0) is required
238 - Peripheral clock as returned by RCC service, should be valid (different from 0).
239 */
240 if ((periphclk != LL_RCC_PERIPH_FREQUENCY_NO)
241 && (USART_InitStruct->BaudRate != 0U))
242 {
243 status = SUCCESS;
244 LL_USART_SetBaudRate(USARTx,
245 periphclk,
246 USART_InitStruct->PrescalerValue,
247 USART_InitStruct->OverSampling,
248 USART_InitStruct->BaudRate);
249
250 /* Check BRR is greater than or equal to 16d */
251 assert_param(IS_LL_USART_BRR_MIN(USARTx->BRR));
252 }
253
254 /*---------------------------- USART PRESC Configuration -----------------------
255 * Configure USARTx PRESC (Prescaler) with parameters:
256 * - PrescalerValue: USART_PRESC_PRESCALER bits according to USART_InitStruct->PrescalerValue value.
257 */
258 LL_USART_SetPrescaler(USARTx, USART_InitStruct->PrescalerValue);
259 }
260 /* Endif (=> USART not in Disabled state => return ERROR) */
261
262 return (status);
263 }
264
265 /**
266 * @brief Set each @ref LL_USART_InitTypeDef field to default value.
267 * @param USART_InitStruct pointer to a @ref LL_USART_InitTypeDef structure
268 * whose fields will be set to default values.
269 * @retval None
270 */
271
LL_USART_StructInit(LL_USART_InitTypeDef * USART_InitStruct)272 void LL_USART_StructInit(LL_USART_InitTypeDef *USART_InitStruct)
273 {
274 /* Set USART_InitStruct fields to default values */
275 USART_InitStruct->PrescalerValue = LL_USART_PRESCALER_DIV1;
276 USART_InitStruct->BaudRate = USART_DEFAULT_BAUDRATE;
277 USART_InitStruct->DataWidth = LL_USART_DATAWIDTH_8B;
278 USART_InitStruct->StopBits = LL_USART_STOPBITS_1;
279 USART_InitStruct->Parity = LL_USART_PARITY_NONE ;
280 USART_InitStruct->TransferDirection = LL_USART_DIRECTION_TX_RX;
281 USART_InitStruct->HardwareFlowControl = LL_USART_HWCONTROL_NONE;
282 USART_InitStruct->OverSampling = LL_USART_OVERSAMPLING_16;
283 }
284
285 /**
286 * @brief Initialize USART Clock related settings according to the
287 * specified parameters in the USART_ClockInitStruct.
288 * @note As some bits in USART configuration registers can only be written when
289 * the USART is disabled (USART_CR1_UE bit =0), USART Peripheral should be in disabled state prior calling
290 * this function. Otherwise, ERROR result will be returned.
291 * @param USARTx USART Instance
292 * @param USART_ClockInitStruct pointer to a @ref LL_USART_ClockInitTypeDef structure
293 * that contains the Clock configuration information for the specified USART peripheral.
294 * @retval An ErrorStatus enumeration value:
295 * - SUCCESS: USART registers related to Clock settings are initialized according
296 * to USART_ClockInitStruct content
297 * - ERROR: Problem occurred during USART Registers initialization
298 */
LL_USART_ClockInit(USART_TypeDef * USARTx,const LL_USART_ClockInitTypeDef * USART_ClockInitStruct)299 ErrorStatus LL_USART_ClockInit(USART_TypeDef *USARTx, const LL_USART_ClockInitTypeDef *USART_ClockInitStruct)
300 {
301 ErrorStatus status = SUCCESS;
302
303 /* Check USART Instance and Clock signal output parameters */
304 assert_param(IS_UART_INSTANCE(USARTx));
305 assert_param(IS_LL_USART_CLOCKOUTPUT(USART_ClockInitStruct->ClockOutput));
306
307 /* USART needs to be in disabled state, in order to be able to configure some bits in
308 CRx registers */
309 if (LL_USART_IsEnabled(USARTx) == 0U)
310 {
311 /* Ensure USART instance is USART capable */
312 assert_param(IS_USART_INSTANCE(USARTx));
313
314 /* Check clock related parameters */
315 assert_param(IS_LL_USART_CLOCKPOLARITY(USART_ClockInitStruct->ClockPolarity));
316 assert_param(IS_LL_USART_CLOCKPHASE(USART_ClockInitStruct->ClockPhase));
317 assert_param(IS_LL_USART_LASTBITCLKOUTPUT(USART_ClockInitStruct->LastBitClockPulse));
318
319 /*---------------------------- USART CR2 Configuration -----------------------
320 * Configure USARTx CR2 (Clock signal related bits) with parameters:
321 * - Clock Output: USART_CR2_CLKEN bit according to USART_ClockInitStruct->ClockOutput value
322 * - Clock Polarity: USART_CR2_CPOL bit according to USART_ClockInitStruct->ClockPolarity value
323 * - Clock Phase: USART_CR2_CPHA bit according to USART_ClockInitStruct->ClockPhase value
324 * - Last Bit Clock Pulse Output: USART_CR2_LBCL bit according to USART_ClockInitStruct->LastBitClockPulse value.
325 */
326 MODIFY_REG(USARTx->CR2,
327 USART_CR2_CLKEN | USART_CR2_CPHA | USART_CR2_CPOL | USART_CR2_LBCL,
328 USART_ClockInitStruct->ClockOutput | USART_ClockInitStruct->ClockPolarity |
329 USART_ClockInitStruct->ClockPhase | USART_ClockInitStruct->LastBitClockPulse);
330 }
331 /* Else (USART not in Disabled state => return ERROR */
332 else
333 {
334 status = ERROR;
335 }
336
337 return (status);
338 }
339
340 /**
341 * @brief Set each field of a @ref LL_USART_ClockInitTypeDef type structure to default value.
342 * @param USART_ClockInitStruct pointer to a @ref LL_USART_ClockInitTypeDef structure
343 * whose fields will be set to default values.
344 * @retval None
345 */
LL_USART_ClockStructInit(LL_USART_ClockInitTypeDef * USART_ClockInitStruct)346 void LL_USART_ClockStructInit(LL_USART_ClockInitTypeDef *USART_ClockInitStruct)
347 {
348 /* Set LL_USART_ClockInitStruct fields with default values */
349 USART_ClockInitStruct->ClockOutput = LL_USART_CLOCK_DISABLE;
350 USART_ClockInitStruct->ClockPolarity = LL_USART_POLARITY_LOW; /* Not relevant when ClockOutput =
351 LL_USART_CLOCK_DISABLE */
352 USART_ClockInitStruct->ClockPhase = LL_USART_PHASE_1EDGE; /* Not relevant when ClockOutput =
353 LL_USART_CLOCK_DISABLE */
354 USART_ClockInitStruct->LastBitClockPulse = LL_USART_LASTCLKPULSE_NO_OUTPUT; /* Not relevant when ClockOutput =
355 LL_USART_CLOCK_DISABLE */
356 }
357
358 /**
359 * @}
360 */
361
362 /**
363 * @}
364 */
365
366 /**
367 * @}
368 */
369
370 #endif /* USART1 */
371
372 /**
373 * @}
374 */
375
376 #endif /* USE_FULL_LL_DRIVER */
377
378
379
