STM32F722CV - USART1 RX Interrupt not working.

[�?Ars]

Hello, I am trying to communicate MCU with using USART1 but interrupt never triggered in MCU.

First I am using some definitions. Here is definitions for USART1.

#define USART1_PINS_PORT		GPIOA
#define USART1_RX_PIN			GPIO_PIN_10
#define USART1_TX_PIN			GPIO_PIN_9
#define USART1_ALTERNATE_FUNC		GPIO_AF7_USART1
#define USART1_GPIO_CLK_ENABLE()	__HAL_RCC_GPIOA_CLK_ENABLE()
#define USART1_CLK_ENABLE()			__HAL_RCC_USART1_CLK_ENABLE()
#define USART1_IRQ_NUM			USART1_IRQn
 
UART_HandleTypeDef USART1_Handle; /* Put USART to asynchronous mode */

My init function is :

void ml45_uart_init(void)
{
	USART1_Handle.Instance = USART1;
	USART1_Handle.Init.BaudRate = 115200;
	USART1_Handle.Init.Mode = USART_MODE_TX_RX;
	USART1_Handle.Init.WordLength = USART_WORDLENGTH_8B;
	USART1_Handle.Init.StopBits = USART_STOPBITS_1;
	USART1_Handle.Init.Parity = USART_PARITY_NONE;
	USART1_Handle.Init.HwFlowCtl = UART_HWCONTROL_NONE;
	USART1_Handle.Init.OverSampling = UART_OVERSAMPLING_16;
	USART1_Handle.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
	USART1_Handle.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT; 
	
	if ( HAL_UART_DeInit(&USART1_Handle) != HAL_OK )
	{
		while ( 1 )
		{
			/* UART INITIALIZATION FAILED */
		}
	}
	
	if ( HAL_UART_Init(&USART1_Handle) != HAL_OK )
	{
		while ( 1 )
		{
			/* UART INITIALIZATION FAILED */
		}
	}
}

And here is my msp init and msp deinit function :

void HAL_UART_MspInit(UART_HandleTypeDef *husart)
{
	/* Enable Peripherals */
	USART1_CLK_ENABLE();
	USART1_GPIO_CLK_ENABLE();
	
	GPIO_InitTypeDef GPIO_InitStructure;
	
	/* Init RX TX Pin */
	GPIO_InitStructure.Pin = USART1_TX_PIN | USART1_RX_PIN;
	GPIO_InitStructure.Mode = GPIO_MODE_AF_PP;
	GPIO_InitStructure.Pull = GPIO_NOPULL;
	GPIO_InitStructure.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
	GPIO_InitStructure.Alternate = USART1_ALTERNATE_FUNC;
	HAL_GPIO_Init(USART1_PINS_PORT, &GPIO_InitStructure);
 
	
	/* Arrange interrupt priority then enable it for USART1 */
	__HAL_USART_ENABLE_IT(husart, USART_IT_RXNE);
	__HAL_USART_CLEAR_IT(husart, USART_IT_TXE);
	HAL_NVIC_SetPriority(USART1_IRQ_NUM, 0, 1);
	HAL_NVIC_EnableIRQ(USART1_IRQ_NUM);
}
 
/**
  * @brief UART MSP De-Initialization
  *        This function frees the hardware resources used in this example:
  *          - Disable the Peripheral's clock
  *          - Revert GPIO and NVIC configuration to their default state
  * @param huart: UART handle pointer
  * @retval None
  */
void HAL_UART_MspDeInit(UART_HandleTypeDef *husart)
{
	(void)husart;
	
	__HAL_RCC_USART1_FORCE_RESET();
	__HAL_RCC_USART1_RELEASE_RESET();
	
	HAL_GPIO_DeInit(USART1_PINS_PORT, USART1_RX_PIN);
	HAL_GPIO_DeInit(USART1_PINS_PORT, USART1_TX_PIN);
	
	HAL_NVIC_DisableIRQ(USART1_IRQ_NUM);
}

And lastly here is my interrupt routine :

void USART1_IRQHandler(void)
{
	volatile uint32_t ISR_shadow = USART1_Handle.Instance->ISR;
}

I put debug point in USART1_IRQHandler. Program can not reach at this point.

I am sure with the sending side of USART. This part is working.

So What is mcu's problem ? Is mine initialization code is wrong ?

Thanks for answers.

[Tesla DeLorean]

Perhaps it doesn't actually receive anything? Does it work in polled mode? Can you see RXNE asserting, or does the USART indicate an error state, like parity, noise or framing that you need to clear?

If you enable the TXE interrupt, does it enter then?

Using C++ or a .cpp file name? could be a name mangling issue.

[�?Ars]

Thanks for your response,

When I call HAL_UART_Transmit_IT after initialize the uart, ISR is working.

But when I track the TX signal from scope. There is not any TX signal.

So What can be wrong in this situation ?

Thanks again.

[Tesla DeLorean]

The IRQ handler would need to call the HAL routines to service the callbacks.

Sorry not familiar with your board/design

[�?Ars]

Okay, lastly,

I change all settings for using USART6.

When I do this, everything is okay. So Is there any difference between USART6 and USART1 ?

[Tesla DeLorean]

>>So Is there any difference between USART6 and USART1 ?

How it is wired on the board, and aspects of the design you haven't shared?

[�?Ars]

PA9 is used for TX pin and PA10 is used for RX pin. Then these pins is connected to connector.

[Tesla DeLorean]

Ok, I can see USART1 PA9/PA10 from your code example, what about the USART6 you're asking for a comparison against?

Is this an ST board, or one designed/built by yourself?

Can you provide a schematic?

[�?Ars]

I am using STM32F746 Discovery kit for test. For USART1, I removed R64 and R133 for using USART1 pins. Then I connect Usb to serial chip to this pins with GND.

Here is its schematics :

https://www.st.com/content/ccc/resource/technical/document/user_manual/f0/14/c1/b9/95/6d/40/4d/DM00190424.pdf/files/DM00190424.pdf/jcr:content/translations/en.DM00190424.pdf