use both I2C Master DMA and UART DMA at once

[Frogram]

Hi all,

I am trying to use I2C DMA as Master and UART DMA

My code is

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim){
 if (c == 1) {
	 HAL_UART_Transmit_DMA(&huart2, (uint8_t *)b, 8);
 } else {
	 /* I2C Transmit code */
 }
 c = 1 - c;
}

and which I tried are (instead of /* I2C Transmit code */) :

// 1. polling, it worked
	 HAL_I2C_Master_Transmit(~~, 50);
	 HAL_I2C_Master_Receive(~~, 50);
// 2. DMA, not worked
 HAL_I2C_Master_Transmit_DMA(~~);
 HAL_I2C_Master_Receive_DMA(~~);
// 3. Mem read dma, not worked
	 HAL_I2C_Mem_Read_DMA(~~);
// 4. Seq DMA, not worked
	 HAL_I2C_Master_Seq_Transmit_DMA(~~, I2C_FIRST_FRAME);
	 HAL_I2C_Master_Seq_Receive_DMA(~~, I2C_LAST_FRAME);

I have no Idea whats wrong and how to solve it

thanks

[Amel NASRI]

Hi @Frogram​ ,

1. Does Uart DMA work properly?
2. Is your initialization code generated with STM32CubeMX? If you are using latest STM32CubeMX version 6.3.0, please make sure to have correct order for HAL_DMA_Init() and peripheral init.

-Amel

[Frogram]

Hi

1. yes, UART DMA works well
2. I used STM32CubeIDE for create .ioc and here is no HAL_DMA_Init() only MX_DMA_Init(). how could I add it?

[Amel NASRI]

Yes it is MX_DMA_Init().

Please make sure that it is called after MX_I2C_Init().

-Amel

[Frogram]

The code was already set as you said. TT