UART STM32L0, Parity bit implementation - c++

Question

I am setting up communication via USART2 Asynchronous to receive my data. Configuration for receive the data is 9600/7bit/1-bit stop/Parity Even/Mode Rx/Tx. The implementation works fine when no parity is implemented. But the specification dictates that even parity should be supported.
If added the parity, I received any value.I do not understand where is the problem.
My configuration is with STMCubeMx for STM32L031K6 nucleo.
void MX_USART2_UART_Init(void)
{
huart2.Instance = USART2;
huart2.Init.BaudRate = 9600;
huart2.Init.WordLength = UART_WORDLENGTH_7B;
huart2.Init.StopBits = UART_STOPBITS_1;
huart2.Init.Parity = UART_PARITY_NONE;
huart2.Init.Mode = UART_MODE_RX;
huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart2.Init.OverSampling = UART_OVERSAMPLING_16;
huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_RXOVERRUNDISABLE_INIT|UART_ADVFEATURE_DMADISABLEONERROR_INIT;
huart2.AdvancedInit.OverrunDisable = UART_ADVFEATURE_OVERRUN_DISABLE;
huart2.AdvancedInit.DMADisableonRxError = UART_ADVFEATURE_DMA_DISABLEONRXERROR;
if (HAL_UART_Init(&huart2) != HAL_OK)
{
Error_Handler();
}
}
void HAL_UART_MspInit(UART_HandleTypeDef* uartHandle)
{
GPIO_InitTypeDef GPIO_InitStruct;
if(uartHandle->Instance==USART2)
{
/* Peripheral clock enable */
__HAL_RCC_USART2_CLK_ENABLE();
/**USART2 GPIO Configuration
PA9 ------> USART2_TX
PA10 ------> USART2_RX
*/
GPIO_InitStruct.Pin = GPIO_PIN_9|GPIO_PIN_10;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF4_USART2;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* Peripheral interrupt init */
HAL_NVIC_SetPriority(USART2_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(USART2_IRQn);
}
}
void HAL_UART_MspDeInit(UART_HandleTypeDef* uartHandle)
{
if(uartHandle->Instance==USART2)
{
/* Peripheral clock disable */
__HAL_RCC_USART2_CLK_DISABLE();
/**USART2 GPIO Configuration
PA9 ------> USART2_TX
PA10 ------> USART2_RX
*/
HAL_GPIO_DeInit(GPIOA, GPIO_PIN_9|GPIO_PIN_10);
/* Peripheral interrupt Deinit*/
HAL_NVIC_DisableIRQ(USART2_IRQn);
}
}
void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct;
/* GPIO Ports Clock Enable */
__HAL_RCC_GPIOA_CLK_ENABLE();
__HAL_RCC_GPIOB_CLK_ENABLE();
/*Configure GPIO pin Output Level */
HAL_GPIO_WritePin(GPIOB, GPIO_PIN_3, GPIO_PIN_RESET);
/*Configure GPIO pin : PB3 */
GPIO_InitStruct.Pin = GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
}
/*********************** interruption **********************/
void HAL_UART_RxCpltCallback(UART_HandleTypeDef *huart)
{
if (huart->Instance == USART2) //current UART
{
Receive();
HAL_UART_Receive_IT(&huart2, Rx_data, 1);
}
}
/******************** Main ******************************/
int main(void)
{
HW_Init();
HAL_UART_Receive_IT(&huart2, Rx_data, 1);
while (1)
{
}
}

Answer 1

When using parity on STM32 series, you need to increase the UART_WORDLENGTH_7B to UART_WORDLENGTH_8B (or UART_WORDLENGTH_9B if you have 8 bits of data).
I just experienced the same problem myself recently. The HAL API should been better at this point...