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Unreadable characters connecting stm32 nucleo with stm32 h7 chip

Associate III


I am trying to send data to a stm32 h743zit6 chip from a stm32 nucleo h743zi that i am connected with. But while i am sending a word, it starts to show strange characters.

I connect the nucleo with USB and using Rx and Tx on CN5 and SWD pins on CN6 with the other stm32 chip so i can send data to it. 

I configure the USART6 of the stm32 h743zi and i use in the code:

  while (1)

    /* USER CODE BEGIN 3 */
	  uint8_t Test[] = "PRUEBA\r\n"; //Data to send
	  HAL_UART_Transmit(&huart6,Test,sizeof(Test),10);// Sending in normal mode

I use Putty with the same bit, parity and baud rate and i see this:


Connection is working for sure, because if there's something wrong, suddenly the IDE shows "st link not connected" and i think usart is well configured because i send some data (bad data, but data),

It is possible that connections are wrong, but, any suggestions of firmware or configurations considerations??




The Nucleo-H743ZI or H743ZI2 ?

Get a scope look at the signals.

Show a schematic or diagram of exactly what you've got wired up, and how the pins are configured. It's probably got ZERO to do with the code fragment shared.

Two boards? Got the ground connected and RX/TX pairs switched?

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Looks like a mismatch between baud rates. Ensure the clock is set correctly.

> nucleo h743zi

The clock on this chip should be from HSE bypass at 8 MHz. Verify that HSE_VALUE = 8000000.

Sounds like you have another custom board with a chip on it.

If you have a scope or logic analyzer, look at the signal.

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Associate III

I think it was something about electronics connections..., I am still working on it, thank you for your replies @TDK @Tesla DeLorean