why HAL_UART_Transmit not working at clocks above 2 MHz?
- October 7, 2019
- 4 replies
- 1135 views
I am using stm32l496, when in stm32cube I set the MSI clock above 2 MHz even if I don't change the Uart clock, when micro exits from lprun mode, HAL_UART_Transmit function not working or prints at a very delayed time for example if it must printed every 20 seconds, it does every 2 minutes, but if i don't use micro in low power mode and always be the run mode, prints correctly.
please help me.
best regards.
sprintf(AA_str,"ReadCounter= %d\r\n",EnLpTick);
HAL_UART_Transmit(&huart1,(uint8_t *)AA_str,strlen(AA_str),100);
HAL_StatusTypeDef HAL_UART_Transmit(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)
{
uint8_t *pdata8bits;
uint16_t *pdata16bits;
uint32_t tickstart;
/* Check that a Tx process is not already ongoing */
if (huart->gState == HAL_UART_STATE_READY)
{
if ((pData == NULL) || (Size == 0U))
{
return HAL_ERROR;
}
__HAL_LOCK(huart);
huart->ErrorCode = HAL_UART_ERROR_NONE;
huart->gState = HAL_UART_STATE_BUSY_TX;
/* Init tickstart for timeout managment*/
tickstart = HAL_GetTick();
huart->TxXferSize = Size;
huart->TxXferCount = Size;
/* In case of 9bits/No Parity transfer, pData needs to be handled as a uint16_t pointer */
if ((huart->Init.WordLength == UART_WORDLENGTH_9B) && (huart->Init.Parity == UART_PARITY_NONE))
{
pdata8bits = NULL;
pdata16bits = (uint16_t *) pData;
}
else
{
pdata8bits = pData;
pdata16bits = NULL;
}
while (huart->TxXferCount > 0U)
{
if (UART_WaitOnFlagUntilTimeout(huart, UART_FLAG_TXE, RESET, tickstart, Timeout) != HAL_OK)
{
return HAL_TIMEOUT;
}
if (pdata8bits == NULL)
{
huart->Instance->TDR = (uint16_t)(*pdata16bits & 0x01FFU);
pdata16bits++;
}
else
{
huart->Instance->TDR = (uint8_t)(*pdata8bits & 0xFFU);
pdata8bits++;
}
huart->TxXferCount--;
}
if (UART_WaitOnFlagUntilTimeout(huart, UART_FLAG_TC, RESET, tickstart, Timeout) != HAL_OK)
{
return HAL_TIMEOUT;
}
/* At end of Tx process, restore huart->gState to Ready */
huart->gState = HAL_UART_STATE_READY;
__HAL_UNLOCK(huart);
return HAL_OK;
}
else
{
return HAL_BUSY;
}
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};
/** Initializes the CPU, AHB and APB busses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
RCC_OscInitStruct.MSIState = RCC_MSI_ON;
RCC_OscInitStruct.MSICalibrationValue = 0;
RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_7;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler();
}
/** Initializes the CPU, AHB and APB busses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV4;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
Error_Handler();
}
PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART1|RCC_PERIPHCLK_LPTIM1;
PeriphClkInit.Usart1ClockSelection = RCC_USART1CLKSOURCE_PCLK2;
PeriphClkInit.Lptim1ClockSelection = RCC_LPTIM1CLKSOURCE_PCLK;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
{
Error_Handler();
}
/** Configure the main internal regulator output voltage
*/
if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1) != HAL_OK)
{
Error_Handler();
}
}
