When the pin assigned to UART, you can't use "UART_CONSOLE_rx_SetDriveMode(UART_CONSOLE_rx_DM_RES_UP" to control the pin.
If you want to change the UART pin drive mode, you need to config the HSIOM to let pin to GPIO.
Thank you for your reply.
Ok, but if I let the pin to GPIO, could you confirm I still can receive characters on UART pin?
No, if the pin configured as GPIO, it can't receive data.
If you want to receive data, you can't control it as a GPIO.
Sorry for my late reply.
Thank you for your help. We decided to let the UART pin as gpio in a way to have the pull-up setting.