Hello all,
I directly copied and pasted the bin file to the board at that time still can be recongnized as a tty interface. However, after status led flashed quickly and I unplugged and plugged the cable again, the tty interface has gone. Also if now I use the Xpresso IDE to flash some other axf to the board. It would show probe cannot be found.
Anyone knows how to get the usb driver back? Thanks a lot.

But it still appears as the bootloader driver,
