I have been using LM Flash Programmer for weeks to program the TM4C device on our custom board. I am using the USB DFU configuration. I made yet another change to the code, entered the dfu command in my TeraTerm window, and then programmed the device. At this point I lost all connection to the device. Nothing happened in TeraTerm when I hit enter. I closed down TeraTerm and opened it up again, and there was no TivaWare COM port listed. I unplugged the USB cable and plugged it back into my laptop, and after several seconds I saw a pop-up telling me "USB Device Not Recognized". I think the TM4C is bricked. How can I unbrick it?