Why I'm unable to use UART to upload a program to NUCLEO L476?

[Prajnyajit]

I'm using Nucleo-L476RG as MCU. I am trying to upload a program to it using UART.

1. I have tried connecting the BOOT0 with VDD.
2. Rx/D0 with Rx of FTDI (USB to TTL cable).
3. Tx/D1 with Tx of FTDI.
4. The ground of FTDI with Ground of Nucleo.

I am using STM32 Flasher to upload the program but am unable to do so. I have tried another way to put MCU into bootloader mode which is pressing the USER button still no result. Why?

[Uwe Bonnes]

Did you try cross connection?

[Prajnyajit]

Yes! Already done. No improvement.

[TDK]

> Rx/D0 with Rx of FTDI (USB to TTL cable).

> Tx/D1 with Tx of FTDI.

RX and TX must be crossed. In other words, the TX signal transmitted by the adapter must be connected to the UART_RX pin on the MCU.

Also note that the onboard ST-Link may be holding the chip in reset. Upgrade firmware or otherwise verify NRST is high.

[Prajnyajit]

checked it all. I think it wont be possible because USB is already connected so first it needs to be desoldered then only serial/UART can be possible.