when trying to connect with the serial port this is the message I got and the uart connection is completely lost and is there any possibility to reestablish the connection?

[Nmv1608]

11:17:48:304 : Serial Port COM8 is successfully opened.

11:17:48:304 : Port configuration: parity = even, baudrate = 9600, data-bit = 8, stop-bit = 1.0, flow-control = off

11:17:48:304 : No Init bits value is : 0 

11:17:48:304 : Sending init command: 

11:17:48:304 : byte 0x7F sent successfully to target

11:17:49:304 : Wait ends after 1 loop, dataready = 0, delay = 1000

11:17:49:305 : Timeout error occured while waiting for acknowledgement.

11:17:49:305 : No response from target received

11:17:49:306 : byte 0x7F sent successfully to target

11:17:49:404 : Wait ends after 1 loop, dataready = 0, delay = 100

11:17:49:405 : Timeout error occured while waiting for acknowledgement.

11:17:49:406 : No response from target received

11:17:49:406 : Error: Activating device: KO. Please, verify the boot mode configuration and check the serial port configuration. Reset your device then try again...

[Imen.D]

Hello @Nmv1608​ ,

Which STM32CubeProgrammer version are using ? If you are using an old version, please try to use the latest version V 2.3.0.

Then, please let us know if the issue still exist with the last version.

Best Regards,

Imen

[Nmv1608]

I tried it with the latest version of STM32CubeProgrammer version 2.3.0, but the problem still exists. Looks like the uart is blocked.

[Imen.D]

Please check the board user manual and AN2606 to verify the connection of connector to the UART bootloader.

[Ozone]

Is the target really in system bootloader mode ?

Are the connections to the target correct ? Check up to the MCU pin.

It is common to need several tries to establish connection.