Nucleo board look at User Manual UM1724 Paragraph 6.8 any help with this line please ? [SB62 and SB63 must be ON, while SB13 and SB14 must be OFF]

[Tesla DeLorean]

What actual model of NUCLEO are you working with?

A lot of the SB (Solder Bridge) options relate to removing pin level conflicts and stubs, and allowing for alternate wiring to Arduino headers, etc.

Here they allow for you to decide what's primary connected to the VCP or Arduino D0/D1 pins, as there are limited options.

Do you want to communicate with the VCP, or a shield using a UART ?

[SEKLAMIN]

thank you for replying i'm working with nucleo_L073RZ

connect another USART to ST-LINK MCU using flying wires between the ST morpho connector and CN3

[Tesla DeLorean]

SB13/SB14 being OFF would allow alternate wiring to CN3 RX/TX pins

[Tesla DeLorean]

Schematics can be found under the "CAD Resources" tabs of most boards

[SEKLAMIN]

thank you sir