当前位置：首页 > news >正文

[STM32U3] 【STM32U385RG 测评】基础任务2 基于低功耗串口测试

news 2026/5/27 22:57:12

根据评测任务，此次测试需要用到低功耗串口，我这里使用lpuart1做为测试口，根据原理图，他接到PA2、PA3

1、串口初始化：

static void MX_LPUART1_UART_Init(void)
{
/* USER CODE BEGIN LPUART1_Init 0 */
/* USER CODE END LPUART1_Init 0 */
/* USER CODE BEGIN LPUART1_Init 1 */
/* USER CODE END LPUART1_Init 1 */
hlpuart1.Instance = LPUART1;
hlpuart1.Init.BaudRate = 115200;
hlpuart1.Init.WordLength = UART_WORDLENGTH_8B;
hlpuart1.Init.StopBits = UART_STOPBITS_1;
hlpuart1.Init.Parity = UART_PARITY_NONE;
hlpuart1.Init.Mode = UART_MODE_TX_RX;
hlpuart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
hlpuart1.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
hlpuart1.Init.ClockPrescaler = UART_PRESCALER_DIV1;
hlpuart1.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
hlpuart1.FifoMode = UART_FIFOMODE_DISABLE;
if (HAL_UART_Init(&hlpuart1) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_SetTxFifoThreshold(&hlpuart1, UART_TXFIFO_THRESHOLD_1_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_SetRxFifoThreshold(&hlpuart1, UART_RXFIFO_THRESHOLD_1_8) != HAL_OK)
{
Error_Handler();
}
if (HAL_UARTEx_DisableFifoMode(&hlpuart1) != HAL_OK)
{
Error_Handler();
}
/* USER CODE BEGIN LPUART1_Init 2 */
#ifdef BOARD_IN_STOP_MODE
LPUART1_EXTI_ENABLE_IT();
#endif /* BOARD_IN_STOP_MODE */
/* USER CODE END LPUART1_Init 2 */
}

2、同时为了显示LED，初始化led2

复制

BSP_LED_Init(LD2);

3、配置低功耗时钟：

复制

void SystemClock_Config_fromSTOP(void)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
uint32_t pFLatency = 0;
/* Get the Oscillators configuration from the internal RCC registers */
HAL_RCC_GetOscConfig(&RCC_OscInitStruct);
/* Wake up on HSI, re-enable PLL with HSI as source */
/* Oscillator configuration unchanged */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/* Get the clock prescalers configuration from the internal RCC registers */
HAL_RCC_GetClockConfig(&RCC_ClkInitStruct, &pFLatency);
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2
|RCC_CLOCKTYPE_PCLK3;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB3CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, pFLatency) != HAL_OK)
{
Error_Handler();
}
}

4、测试程序设计，在主程序中，首先延时2秒，然后开启低功耗串口的接收中断，然后进入低功耗模式，关闭LD2，当有串口数据接收后，周期闪烁，闪烁10次，如果没有数据再次进入，则再次进入低功耗模式。

复制

/* LD2 is on till stop mode */
BSP_LED_On(LD2);
/* wait for two seconds before test start */
HAL_Delay(2000);
/* Disable Debug during Stop mode */
HAL_DBGMCU_DisableDBGStopMode();
/* Enable MCU wake-up by LPUART */
HAL_UARTEx_EnableStopMode(&hlpuart1);
/*##-1- Put UART peripheral in reception process ###########################*/
if (HAL_UART_Receive_IT(&hlpuart1, (uint8_t *)aRxBuffer, RXBUFFERSIZE) != HAL_OK)
{
Error_Handler();
}
/* about to enter STOP mode: switch off LD2 */
BSP_LED_Off(LD2);
/* enter STOP mode */
HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);
/* The board receives the message from the other board. Message reception wakes up the board. */
/* Switch On LD2 */
BSP_LED_On(LD2);
/* At that point, MCU has been awoken: LD2 has been turned back on ; Wake Up based on RXNE flag successful */
SystemClock_Config_fromSTOP();
/* Disable MCU wake-up by LPUART */
HAL_UARTEx_DisableStopMode(&hlpuart1);
#endif /* !BOARD_IN_STOP_MODE */
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
BSP_LED_Off(LD2);
HAL_Delay(500);
BSP_LED_On(LD2);
HAL_Delay(500);
cnt++;
if(cnt >10)
{
/* Disable Debug during Stop mode */
HAL_DBGMCU_DisableDBGStopMode();
/* Enable MCU wake-up by LPUART */
HAL_UARTEx_EnableStopMode(&hlpuart1);
/*##-1- Put UART peripheral in reception process ###########################*/
if (HAL_UART_Receive_IT(&hlpuart1, (uint8_t *)aRxBuffer, RXBUFFERSIZE) != HAL_OK)
{
Error_Handler();
}
/* about to enter STOP mode: switch off LD2 */
BSP_LED_Off(LD2);
/* enter STOP mode */
HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);
/* The board receives the message from the other board. Message reception wakes up the board. */
/* Switch On LD2 */
BSP_LED_On(LD2);
/* At that point, MCU has been awoken: LD2 has been turned back on ; Wake Up based on RXNE flag successful */
SystemClock_Config_fromSTOP();
/* Disable MCU wake-up by LPUART */
HAL_UARTEx_DisableStopMode(&hlpuart1);
cnt = 0;
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */