uart 2 and uart 3 not transmitting in B-U585I-IOT02A

[shivss]

HI 

  am using stm32 B-U585I-IOT02A  dev board in that the uart2 and uart3 are not transmitting the data but its receiving the data . I have set PH 13 and PH 15 high also . but Tx is not working only Rx working

my code

 

 

in this only hello2 getting in my serial terminal.

[Karl Yamashita]

PH13 and PH15 do not have UART peripherals.

Those pins are used to switch between 1 and 2 on the switcher 

Look at the schematic again, you'll see that USART2_TX is PA2 and USART3_TX is PD8

[shivss]

Hi @Karl Yamashita 

   PH 13 and 15 are not uart2 and 3 pins yes but need to use that for on board uart2 and 3 to work according to the user manual , used PA2 and PD8 only for Tx 

 

[Karl Yamashita]

Sorry, I've misinterpreted your "set" to high, as in pulled-up to high for the Tx pins.

If you are receiving on USAT3, then the switcher is configured correctly. So what are you transmitting to?

Also, use strlen to send the correct amount of characters.

HAL_UART_Transmit(&huart2, (uint8_t*)"hello\n", strlen("hello\n"), 100) 

[shivss]

Hi @Karl Yamashita 

  not even receiving on uart3 also .  

HAL_UART_Transmit(&huart2, (uint8_t*)"hello\n", strlen("hello\n"), 100) 

after trying this also not getting output.

 but I found something that PH13 is getting automatically low ? why 

if (rx_buf[0] == 's') 
		{
			HAL_GPIO_WritePin(GPIOH, GPIO_PIN_13, GPIO_PIN_SET);

			HAL_UART_Transmit(&huart2, (uint8_t*) "hello\n", strlen("hello\n"),
					100);
			if (HAL_UART_Transmit(&huart2, (uint8_t*) "hello1\n",
					strlen("hello1\n"), 100) == HAL_OK) {
				HAL_UART_Transmit(&huart1, (uint8_t*) "hello2\n",
						strlen("hello2\n"), 100);
			}
			rx_buf[0] = 0;
			j = 0;
			if (HAL_GPIO_ReadPin(GPIOH, GPIO_PIN_13) == GPIO_PIN_RESET) {
				HAL_UART_Transmit(&huart1, (uint8_t*) "PH13 LOW!\n", 10, 100);
			} else {
				HAL_UART_Transmit(&huart1, (uint8_t*) "PH13 HIGH!\n", 10, 100);
			}
		}

I need to set pin high every time? i don't think so   

output of uart1:

hello2
PH13 LOW!

if I comment the write pin then uart2 is not transmitting  

[Karl Yamashita · Accepted solution]

I have the B-U585I-IOT02A and just tested with USART2. I can get UART2 Tx to work just fine.

I took the STMOD+ and have it on CN3 with Rx and Tx jumped.

I am using VCP (USART1) to receive some string and transmit the string on USART2. Then the callback takes the USART2 string it just received and loops it back to VCP. 

 

I've attached the project that I've just tested with.

[shivss]

Hi @Karl Yamashita 

  Thanks for the help