UART with STM32F4xx Using USB to TTL Converter

[GKim.1]

I want to do UART by connecting USB to TTL converter(PN-USBTTL-FT, FTDI FT232RL) to Tx and Rx of the board pin without using the USB port of the debugger part of STM32F4xx.

The main code is as follows:

uint8_t a = 'a';
 while (1)
 {
HAL_UART_Transmit(&huart2, &a, 1, 10);
HAL_Delay(1000);
}

The debugging board's USB(download port) can receive "aaaaa ..." input every second, but it cannot receive any value from the Tx and Rx pins assigned to CubeMX.

What should I do?

[waclawek.jan]

What board?

How did you connect it to the USB convertor?

Did you connect also ground?

How do you observe it?

Did you test the USB convertor with a loopback?

Can you observe the signals using oscilloscope or LA (logic analyzer)?

JW